Showing 1–21 of 21 results for author: Krech, W

Coherent Rabi response of a charge-phase qubit under microwave irradiation

Authors: V. I. Shnyrkov, D. Born, A. A. Soroka, W. Krech

Abstract: We report on radio-frequency measurements of the charge-phase qubit being under continuous microwave irradiation in the state of weak coupling to a radio-frequency tank circuit. We studied the rf impedance dependence on the two important parameters such as power of microwave irradiation whose frequency is close to the gap between the two lowest qubit energy levels, and temperature of the interna… ▽ More We report on radio-frequency measurements of the charge-phase qubit being under continuous microwave irradiation in the state of weak coupling to a radio-frequency tank circuit. We studied the rf impedance dependence on the two important parameters such as power of microwave irradiation whose frequency is close to the gap between the two lowest qubit energy levels, and temperature of the internal heat bath. We have found that backaction effects of the qubit on the rf tank, and vice versa, tank on the qubit, lead to a negative as well as a positive real part of the qubit impedance Re$Z(ω)$ seen by the tank. We have implemented noise spectroscopy measurements for direct impedance readout at the extreme points corresponding to maximum voltage response and obtained absolute values of about 0.017 $Ω$ for the negative and positive Re$Z(ω)$. Our results demonstrate the existence and persistence of the coherent single- and multi-photon Rabi dynamics of the qubit with both negative and positive dynamic resistance inserted into the tank in the temperature range of 10 to 200 mK. △ Less

Submitted 17 October, 2008; originally announced October 2008.

Comments: 11 pages, 9 figures

Journal ref: Phys. Rev. B 79 (2009) 184522

The quantization of a charge qubit. The role of inductance and gate capacitance

Authors: Ya. S. Greenberg, W. Krech

Abstract: The Hamiltonian of a charge qubit, which consists of two Josephson junctions is found within well known quantum mechanical procedure. The inductance of the qubit is included from the very beginning. It allows a selfconsistent derivation of the current operator in a two state basis. It is shown that the current operator has nonzero nondiagonal matrix elements both in the charge and the eigenstate… ▽ More The Hamiltonian of a charge qubit, which consists of two Josephson junctions is found within well known quantum mechanical procedure. The inductance of the qubit is included from the very beginning. It allows a selfconsistent derivation of the current operator in a two state basis. It is shown that the current operator has nonzero nondiagonal matrix elements both in the charge and the eigenstate basis. It is also shown that the interaction of the qubit with its own LC resonator has a noticeable influence on the qubit energies. The influence of the junctions asymmetry and the gate capacitance on the matrix elements of the current operator and on the qubit energies are calculated. The results obtained in the paper are important for the circuits where two or more charge qubits are coupled with the aid of inductive coil. △ Less

Submitted 28 January, 2006; originally announced January 2006.

Comments: 14 pages, 3 figures

Multiphoton transitions between energy levels in a phase-biased Cooper-pair box

Authors: V. I. Shnyrkov, Th. Wagner, D. Born, S. N. Shevchenko, W. Krech, A. N. Omelyanchouk, E. Il'ichev, H. -G. Meyer

Abstract: We investigated both theoretically and experimentally dynamic features of a phase-biased charge qubit consisting of a single-Cooper-pair transistor closed by a superconducting loop. The effective inductance of the qubit was probed by a high-quality tank circuit. In the presence of a microwave power, with a frequency of the order of the qubit energy level separation, an alteration of the qubit in… ▽ More We investigated both theoretically and experimentally dynamic features of a phase-biased charge qubit consisting of a single-Cooper-pair transistor closed by a superconducting loop. The effective inductance of the qubit was probed by a high-quality tank circuit. In the presence of a microwave power, with a frequency of the order of the qubit energy level separation, an alteration of the qubit inductance was observed. We demonstrate that this effect is caused by the redistribution of the qubit level population. The excitation of the qubit by one-, two-, and three-photon processes was detected. Quantitative agreement between theory and experimental data was found. △ Less

Submitted 28 December, 2005; v1 submitted 25 July, 2005; originally announced July 2005.

Comments: 7 pages, 5 figures; v.2: references added and discussion improved

Journal ref: Phys. Rev. B 73, 024506 (2006)

Dynamic behaviour of Josephson-junction qubits: crossover between Rabi oscillations and Landau-Zener transitions

Authors: S. N. Shevchenko, A. S. Kiyko, A. N. Omelyanchouk, W. Krech

Abstract: We study the dynamic behaviour of a quantum two-level system with periodically varying parameters by solving the master equation for the density matrix. Two limiting cases are considered: multiphoton Rabi oscillations and Landau-Zener transitions. The approach is applied to the description of the dynamics of superconducting qubits. In particular, the case of the interferometer-type charge qubit… ▽ More We study the dynamic behaviour of a quantum two-level system with periodically varying parameters by solving the master equation for the density matrix. Two limiting cases are considered: multiphoton Rabi oscillations and Landau-Zener transitions. The approach is applied to the description of the dynamics of superconducting qubits. In particular, the case of the interferometer-type charge qubit with periodically varying parameters (gate voltage or magnetic flux) is investigated. The time-averaged energy level populations are calculated as funtions of the qubit's control parameters. △ Less

Submitted 21 December, 2004; originally announced December 2004.

Comments: 7 pages with 5 figures

Journal ref: Low Temp. Phys. 31, 569 (2005)

Radio-Frequency Method for Investigation of Quantum Properties of Superconducting Structures

Authors: E. Il'ichev, A. Yu. Smirnov, M. Grajcar, A. Izmalkov, D. Born, N. Oukhanski, Th. Wagner, W. Krech, H. -G. Meyer, A. M. Zagoskin

Abstract: We implement the impedance measurement technique (IMT) for characterization of interferometer-type superconducting qubits. In the framework of this method, the interferometer loop is inductively coupled to a high-quality tank circuit. We show that the IMT is a powerful tool to study a response of externally controlled two-level system to different types of excitations. Conclusive information abo… ▽ More We implement the impedance measurement technique (IMT) for characterization of interferometer-type superconducting qubits. In the framework of this method, the interferometer loop is inductively coupled to a high-quality tank circuit. We show that the IMT is a powerful tool to study a response of externally controlled two-level system to different types of excitations. Conclusive information about qubits is obtained from the read-out of the tank properties. △ Less

Submitted 23 June, 2004; v1 submitted 23 February, 2004; originally announced February 2004.

Comments: 10 pages, 10 figures;to be published in Fizika Nizkikh Temperatur (Low Temperature Physics); v3: minor polishing; final

Journal ref: Fizika Nizkikh Temperatur 30, 823 (2004)

Reading-out the state inductively and microwave spectroscopy of an interferometer-type charge qubit

Authors: D. Born, V. I. Shnyrkov, W. Krech, Th. Wagner, E. Il'ichev, M. Grajcar, U. Huebner, H. -G. Meyer

Abstract: We implemented experimentally an interferometer-type charge qubit consisting of a single-Cooper-pair transistor closed by a superconducting loop that is in flip-chip configuration inductively coupled to a radio frequency tank circuit. The tank permits to readout the qubit state, acting as inductance measuring apparatus. By applying continuous microwave power to the quantum device, we observed in… ▽ More We implemented experimentally an interferometer-type charge qubit consisting of a single-Cooper-pair transistor closed by a superconducting loop that is in flip-chip configuration inductively coupled to a radio frequency tank circuit. The tank permits to readout the qubit state, acting as inductance measuring apparatus. By applying continuous microwave power to the quantum device, we observed inductance alterations caused by redistributions of the energy level populations. From the measured data, we extracted the energy gap between ground and upper levels as a function of the transistor quasicharge as well as the Josephson phase across both junctions. △ Less

Submitted 30 September, 2004; v1 submitted 30 December, 2003; originally announced December 2003.

Comments: 4 pages, 5 figures, revised version, to appear in PRB Rapid Comm

Journal ref: Phys. Rev. B 70, 180501 (2004)

Observation of macroscopic Landau-Zener transitions in a superconducting device

Authors: A. Izmalkov, M. Grajcar, E. Il'ichev, N. Oukhanski, Th. Wagner, H. -G. Meyer, W. Krech, M. H. S. Amin, Alec Maassen van den Brink, A. M. Zagoskin

Abstract: A two-level system traversing a level anticrossing has a small probability to make a so-called Landau-Zener (LZ) transition between its energy bands, in deviation from simple adiabatic evolution. This effect takes on renewed relevance due to the observation of quantum coherence in superconducting qubits (macroscopic "Schrodinger cat" devices). We report an observation of LZ transitions in an Al… ▽ More A two-level system traversing a level anticrossing has a small probability to make a so-called Landau-Zener (LZ) transition between its energy bands, in deviation from simple adiabatic evolution. This effect takes on renewed relevance due to the observation of quantum coherence in superconducting qubits (macroscopic "Schrodinger cat" devices). We report an observation of LZ transitions in an Al three-junction qubit coupled to a Nb resonant tank circuit. △ Less

Submitted 30 January, 2004; v1 submitted 21 July, 2003; originally announced July 2003.

Comments: REVTeX4, 4pp., 4 EPS figures. v2: clarifications added; final, to appear in EPL

Journal ref: Europhys. Lett. 65, 844 (2004)

Low-frequency measurement of the tunneling amplitude in a flux qubit

Authors: M. Grajcar, A. Izmalkov, E. Il'ichev, Th. Wagner, N. Oukhanski, U. Huebner, T. May, I. Zhilyaev, H. E. Hoenig, Ya. S. Greenberg, V. I. Shnyrkov, D. Born, W. Krech, H. -G. Meyer, Alec Maassen van den Brink, M. H. S. Amin

Abstract: We have observed signatures of resonant tunneling in an Al three-junction qubit, inductively coupled to a Nb LC tank circuit. The resonant properties of the tank oscillator are sensitive to the effective susceptibility (or inductance) of the qubit, which changes drastically as its flux states pass through degeneracy. The tunneling amplitude is estimated from the data. We find good agreement with… ▽ More We have observed signatures of resonant tunneling in an Al three-junction qubit, inductively coupled to a Nb LC tank circuit. The resonant properties of the tank oscillator are sensitive to the effective susceptibility (or inductance) of the qubit, which changes drastically as its flux states pass through degeneracy. The tunneling amplitude is estimated from the data. We find good agreement with the theoretical predictions in the regime of their validity. △ Less

Submitted 12 January, 2004; v1 submitted 31 March, 2003; originally announced March 2003.

Comments: REVTeX4, 3pp., 3 EPS figures. v2: new sample, textual clarifications. v3: minor polishing; final, to appear in PRB Rapids

Journal ref: Phys. Rev. B 69, 060501(R) (2004)

Method for direct observation of coherent quantum oscillations in a superconducting phase qubit

Authors: Ya. S. Greenberg, A. Izmalkov, M. Grajcar, E. Il'ichev, W. Krech, H. -G. Meyer

Abstract: Time-domain observations of coherent oscillations between quantum states in mesoscopic superconducting systems were so far restricted to restoring the time-dependent probability distribution from the readout statistics. We propose a new method for direct observation of Rabi oscillations in a phase qubit. The external source, typically in GHz range, induces transitions between the qubit levels. T… ▽ More Time-domain observations of coherent oscillations between quantum states in mesoscopic superconducting systems were so far restricted to restoring the time-dependent probability distribution from the readout statistics. We propose a new method for direct observation of Rabi oscillations in a phase qubit. The external source, typically in GHz range, induces transitions between the qubit levels. The resulting Rabi oscillations of supercurrent in the qubit loop are detected by a high quality resonant tank circuit, inductively coupled to the phase qubit. Detailed calculation for zero and non-zero temperature are made for the case of persistent current qubit. According to the estimates for dephasing and relaxation times, the effect can be detected using conventional rf circuitry, with Rabi frequency in MHz range. △ Less

Submitted 23 October, 2002; v1 submitted 7 August, 2002; originally announced August 2002.

Comments: 5 pages, 1 figure, to appear in Phys.Rev.B

Journal ref: Phys. Rev. B 66, 224511 (2002)

Low-frequency characterization of quantum tunneling in flux qubits

Authors: Ya. S. Greenberg, A. Izmalkov, M. Grajcar, E. Il'ichev, W. Krech, H. -G. Meyer, M. H. S. Amin, Alec Maassen van den Brink

Abstract: We propose to investigate flux qubits by the impedance measurement technique (IMT), currently used to determine the current--phase relation in Josephson junctions. We analyze in detail the case of a high-quality tank circuit coupled to a persistent-current qubit, to which IMT was successfully applied in the classical regime. It is shown that low-frequency IMT can give considerable information ab… ▽ More We propose to investigate flux qubits by the impedance measurement technique (IMT), currently used to determine the current--phase relation in Josephson junctions. We analyze in detail the case of a high-quality tank circuit coupled to a persistent-current qubit, to which IMT was successfully applied in the classical regime. It is shown that low-frequency IMT can give considerable information about the level anticrossing, in particular the value of the tunneling amplitude. An interesting difference exists between applying the ac bias directly to the tank and indirectly via the qubit. In the latter case, a convenient way to find the degeneracy point in situ is described. Our design only involves existing technology, and its noise tolerance is quantitatively estimated to be realistic. △ Less

Submitted 3 December, 2002; v1 submitted 5 August, 2002; originally announced August 2002.

Comments: 6 pages, 11 figures, to appear in Phys.Rev.B

Journal ref: Phys. Rev. B 66, 214525 (2002)

Theory of phase-locking in generalized hybrid Josephson junction arrays

Authors: Michael Basler, Wolfram Krech, Konstantin Yu. Platov

Abstract: A recently proposed scheme for the analytical treatment of the dynamics of two-dimensional hybrid Josephson junction arrays is extended to a class of generalized hybrid arrays with ''horizontal'' shunts involving a capacitive as well as an inductive component. This class of arrays is of special interest, because the internal cell coupling has been shown numerically to favor in-phase synchronizat… ▽ More A recently proposed scheme for the analytical treatment of the dynamics of two-dimensional hybrid Josephson junction arrays is extended to a class of generalized hybrid arrays with ''horizontal'' shunts involving a capacitive as well as an inductive component. This class of arrays is of special interest, because the internal cell coupling has been shown numerically to favor in-phase synchronization for certain parameter values. As a result, we derive limits on the circuit design parameters for realizing this state. In addition, we obtain formulas for the flux-dependent frequency including flux-induced switching processes between the in-phase and anti-phase oscillation regime. The treatment covers unloaded arrays as well as arrays shunted via an external load. △ Less

Submitted 24 May, 1996; originally announced May 1996.

Comments: 24 pages, REVTeX, 5 Postscript figures, Subm. to Phys. Rev. B

Intrinsic mechanism of phase locking in two-dimensional Josephson junction networks in presence of an external magnetic field

Authors: W. Krech, K. Yu. Platov

Abstract: We present numerical simulations of the dynamics of two-dimensional Josephson junction arrays to study the mechanism of mutual phase locking. We show that in the presence of an external magnetic field two mechanisms are playing a role in phase locking: feedback through the external load and internal coupling between rows due to microwave currents induced by the field. We have found the parameter… ▽ More We present numerical simulations of the dynamics of two-dimensional Josephson junction arrays to study the mechanism of mutual phase locking. We show that in the presence of an external magnetic field two mechanisms are playing a role in phase locking: feedback through the external load and internal coupling between rows due to microwave currents induced by the field. We have found the parameter values (junction capacitance, cell loop inductance, impedance of the external load) for which the interplay of both these mechanisms leads to the in-phase solution. The case of unshunted arrays is discussed as well. △ Less

Submitted 28 March, 1996; originally announced March 1996.

Comments: 13 pages, incl. 6 ps figures, Subm. to Europhysics Letters

Anti-phase locking in a two-dimensional Josephson junction array

Authors: Michael Basler, Wolfram Krech, Konstantin Yu. Platov

Abstract: We consider theoretically phase locking in a simple two-dimensional Josephson junction array consisting of two loops coupled via a joint line transverse to the bias current. Ring inductances are supposed to be small, and special emphasis is taken on the influence of external flux. Is is shown, that in the stable oscillation regime both cells oscillate with a phase shift equal to $π$ (i.e. anti-p… ▽ More We consider theoretically phase locking in a simple two-dimensional Josephson junction array consisting of two loops coupled via a joint line transverse to the bias current. Ring inductances are supposed to be small, and special emphasis is taken on the influence of external flux. Is is shown, that in the stable oscillation regime both cells oscillate with a phase shift equal to $π$ (i.e. anti-phase). This result may explain the low radiation output obtained so far in two-dimensional Josephson junction arrays experimentally. △ Less

Submitted 6 March, 1996; originally announced March 1996.

Comments: 11 pages, REVTeX, 1 Postscript figure, Subm. to Appl. Phys. Lett

Tunneling through ultrasmall NIS junctions in terms of Andreev reflection: a nonlinear response approach

Authors: A. Hädicke, W. Krech

Abstract: The Andreev current through an ultrasmall NIS junction is calculated in a systematic way by means of a nonlinear response approach basing on the elementary Hamiltonian of quasiparticle tunneling. The voltage dependence of current and differential conductance as well as the Andreev conductance are derived for low- and high-impedance environments, respectively. The Andreev current through an ultrasmall NIS junction is calculated in a systematic way by means of a nonlinear response approach basing on the elementary Hamiltonian of quasiparticle tunneling. The voltage dependence of current and differential conductance as well as the Andreev conductance are derived for low- and high-impedance environments, respectively. △ Less

Submitted 12 April, 1995; originally announced April 1995.

Comments: 8 pages, RevTeX, 4 Figures (uuencoded gz-compressed tar-file)

Report number: JE-FKS-95-3

Nonlinear Response Approach to Cooper Pair Tunneling in Ultrasmall SIS Junctions

Authors: A. Hädicke, W. Krech

Abstract: Single-charge tunneling in ultrasmall voltage biased SIS junctions in a high-impedance electromagnetic environment is considered. The Cooper pair current is calculated at T=0 on the basis of the elementary tunnel Hamiltonian for quasiparticles. Therefore, the transfer of Cooper pairs emerges automatically as an effect of higher order perturbation theory. The supercurrent also depends on the diss… ▽ More Single-charge tunneling in ultrasmall voltage biased SIS junctions in a high-impedance electromagnetic environment is considered. The Cooper pair current is calculated at T=0 on the basis of the elementary tunnel Hamiltonian for quasiparticles. Therefore, the transfer of Cooper pairs emerges automatically as an effect of higher order perturbation theory. The supercurrent also depends on the dissipative part of the Josephson current amplitude. △ Less

Submitted 15 March, 1995; originally announced March 1995.

Comments: 9 pages, RevTeX, 2 figures appended

Report number: AKS-10

THEORY OF PHASE-LOCKING IN SMALL JOSEPHSON JUNCTION CELLS

Authors: M. Basler, W. Krech, K. Yu. Platov

Abstract: Within the RSJ model, we performed a theoretical analysis of phase-locking in elementary strongly coupled Josephson junction cells. For this purpose, we developed a systematic method allowing the investigation of phase-locking in cells with small but non-vanishing loop inductance.The voltages across the junctions are found to be locked with very small phase difference for almost all values of exte… ▽ More Within the RSJ model, we performed a theoretical analysis of phase-locking in elementary strongly coupled Josephson junction cells. For this purpose, we developed a systematic method allowing the investigation of phase-locking in cells with small but non-vanishing loop inductance.The voltages across the junctions are found to be locked with very small phase difference for almost all values of external flux. However, the general behavior of phase-locking is found to be just contrary to that according to weak coupling. In case of strong coupling there is nearly no influence of external magnetic flux on the phases, but the locking-frequency becomes flux-dependent. The influence of parameter splitting is considered as well as the effect of small capacitive shunting of the junctions. Strongly coupled cells show synchronization even for large parameter splitting. Finally, a study of the behavior under external microwave radiation shows that the frequency locking-range becomes strongly flux-dependent, whereas the locking frequency itself turns out to be flux-independent. △ Less

Submitted 13 February, 1995; originally announced February 1995.

Comments: 26 pages, REVTEX, 9 PS figures appended in uuencoded form at the end, submitted to Phys. Rev. B.

Report number: JE-FKS-95-1

On Thermometer Operation of Ultrasmall Tunnel Junctions

Authors: H. -O. Müller, A. Hädicke, W. Krech

Abstract: The temperature dependence of the I-V characteristics of many single-electron tunneling devices enable thermometer operation of these systems. We investigate two normal conducting kinds of them, {\sl (a)} a single junction in a high-impedance environment, and {\sl (b)} a double junction. The characteristics of both devices show a crossover from Coulomb blockade at low temperatures to ohmic behav… ▽ More The temperature dependence of the I-V characteristics of many single-electron tunneling devices enable thermometer operation of these systems. We investigate two normal conducting kinds of them, {\sl (a)} a single junction in a high-impedance environment, and {\sl (b)} a double junction. The characteristics of both devices show a crossover from Coulomb blockade at low temperatures to ohmic behavior at high temperatures. The related differential conductivity dip allows the determination of the junctions temperature. Both configurations {\sl (a)} and {\sl (b)} are expected to work at least within the range $0.5\leβE_{\rm C}\le 10$, where $E_{\rm C}$ is the Coulomb energy of the system under investigation. We present an analytical solution for both low- and high-temperature case of {\sl (a)} and {\sl (b)} as well as numerical results and their fit, including the effect of co-tunneling in case of a double junction. △ Less

Submitted 13 October, 1994; originally announced October 1994.

Comments: 11 pages + 8 figures, REVTeX 3.0, JE-FKS-94-5 8 pages of Postscript figures appended, The numbering of the figures is 1, 2, 3, 4, 5a, 5b, 5c and 6

Journal ref: phys.stat.sol. b 188(2), 667-77 (1995)

Coherent States of Two-dimensional Josephson Junction Networks

Authors: W. Krech, K. Yu. Platov

Abstract: We have investigated numerically the phase--locking behavior of two-dimensional Josephson junction arrays,taking into account a finite inductance ($l\stackrel{>}{\sim}1$) of the unit cell and external magnetic fields. Within this model we demonstrate the existence of multi--valued {\it I--V} curves of the network. Different branches of the {\it I--V} curve correspond to "in--phase" and "anti--ph… ▽ More We have investigated numerically the phase--locking behavior of two-dimensional Josephson junction arrays,taking into account a finite inductance ($l\stackrel{>}{\sim}1$) of the unit cell and external magnetic fields. Within this model we demonstrate the existence of multi--valued {\it I--V} curves of the network. Different branches of the {\it I--V} curve correspond to "in--phase" and "anti--phase" coherent states with high and low levels of output power, respectively. The arrays show remarkable hysteretic transitions between these states under influence of external magnetic fluxes in the range $ - Φ_0/4 < Φ_{ext} < Φ_0/4 $. △ Less

Submitted 23 June, 1994; originally announced June 1994.

Comments: 8 pages + 13 figures appended as uuencodes files, Standard LaTeX, Emails: owk@rz.uni-jena.de, okp@rz.uni-jena.de

Report number: JE-FKS-94-4

Microwave--Driven SET--Box with Superconducting Island

Authors: A. Hädicke, W. Krech

Abstract: The effect of a high--frequency microwave irradiation on the averaged stationary charge in a single--electron tunneling box (SET--box) with superconducting island is investigated. The resulting $\langle Q\rangle$--$Q_g$ characteristics are modified compared with those from the well--known constant voltage--driven box. It can be shown that there is a cross--over from the 2e--periodic regime in… ▽ More The effect of a high--frequency microwave irradiation on the averaged stationary charge in a single--electron tunneling box (SET--box) with superconducting island is investigated. The resulting $\langle Q\rangle$--$Q_g$ characteristics are modified compared with those from the well--known constant voltage--driven box. It can be shown that there is a cross--over from the 2e--periodic regime in $Q_g$ corresponding to the parity effect to 1e--periodic behavior not only with increasing temperature but also with increasing irradiation amplitude. △ Less

Submitted 15 June, 1994; originally announced June 1994.

Comments: 10 pages + 7 figures, REVTeX 3.0, JE-FKS-94-3 4 pages of Postscript figures appended

Phase-Locking in Strongly Coupled Squid Cells

Authors: M. Basler, W. Krech, K. Yu. Platov

Abstract: Within the RSJ model we performed an analytical and numerical investigation of SQUID cells consisting of two Josephson junctions shunted by an extremely small inductance leading to strong coupling of the elements. Contrary to the well-known behavior of cells shunted by a high inductance voltage phases of the junctions are locked with very small phase difference for almost all values of external… ▽ More Within the RSJ model we performed an analytical and numerical investigation of SQUID cells consisting of two Josephson junctions shunted by an extremely small inductance leading to strong coupling of the elements. Contrary to the well-known behavior of cells shunted by a high inductance voltage phases of the junctions are locked with very small phase difference for almost all values of external flux. Only for external flux in the vicinity of half a flux quantum phase difference rises rapidly to $π$. △ Less

Submitted 11 April, 1994; originally announced April 1994.

Comments: 11 pages, LaTeX, report JENA-FKS-94-2

Elastic Co--Tunneling in a 1D Quantum Hole Approach

Authors: Heinz-Olaf Muller, Andreas Hadicke, Wolfram Krech

Abstract: The influence of the phases of tunneling matrix elements on the rate of the elastic co--tunneling at an ultrasmall normal--conducting double--junction is studied in a simple quantum--hole approach at zero temperature. The results are compared with experimental data. The influence of the phases of tunneling matrix elements on the rate of the elastic co--tunneling at an ultrasmall normal--conducting double--junction is studied in a simple quantum--hole approach at zero temperature. The results are compared with experimental data. △ Less

Submitted 3 March, 1994; originally announced March 1994.

Comments: 8 pages, REVTeX v3.0

Journal ref: Phys. Lett. A 187, 337--40 (1994)