Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Modern Physics Letters B

HIGHER-ORDER SQUEEZING DEGREE IN MESOSCOPIC JOSEPHSON JUNCTION IN THE PRESENCE OF NONCLASSICAL RADIATION FIELD

Vasile A. Popescu

Published Mar 10, 2000• 2 citations
Publisher

Abstract

Higher-order squeezing degree in mesoscopic Josephson junction of a circular superconducting ring can be improved if the electromagnetic field is initially in a successive squeezed vacuum state. We compare our method with the usual procedure for higher-order squeezing and consider the effect of different small inductances on the 2Nth-order squeezing degree for quantum current.

DOI
10.1142/s021798490000029x

Related papers

INTERACTION OF MESOSCOPIC JOSEPHSON JUNCTION WITH A SUCCESSIVE SQUEEZED COHERENT FIELD

Vasile A. Popescu

Signal-to-quantum noise ratio for quantum current in mesoscopic Josephson junction of a circular superconducting ring can be improved if the electromagnetic field is in a successive squeezed coherent state. The mesoscopic Josephson junctions can feel the difference between the successive squeezed coherent states and other types of squeezed coherent states because their current–voltage Shapiro steps are different. We compare our method with another procedure for superposition of two squeezed coherent states (a squeezed even coherent state) and consider the effect of different large inductances on the supercurrent.

Modern Physics Letters B•Jul 10, 2000•0 citations

SUPERPOSITIONS OF COHERENT STATES AND SQUEEZING EFFECTS IN A MESOSCOPIC JOSEPHSON JUNCTION

Jian Zou, Bin Shao

We consider a mesoscopic Josephson junction in a circular superconducting ring which encloses a magneto static flux. It is shown that with the junction being initially prepared in its lowest energy level the state of the junction can evolve in a quantum superposition of two coherent states, and squeezing can exist in such system.

International Journal of Modern Physics B•Mar 30, 1999•10 citations

Squeezing Properties in Mesoscopic Josephson Junction with Nonclassical Radiation Field

Shao Bin, Zou Jian, Qian‐Shu Li

We consider a system of mesoscopic Josephson junction interacting with nonclassical radiation field and investigate any order squeezing for the mesoscopic Josephson junction subsystem. Our results show that if the field is initially prepared in a squeezed vacuum and the junction is in its lowest energy state (the vacuum state), then as the time evolves the Josephson junction subsystem can exhibit any order squeezing.

Modern Physics Letters B•Jul 10, 1998•7 citations

Mesoscopic Josephson junctions in the presence of nonclassical electromagnetic fields

Apostol Vourdas

Circular superconducting devices with mesoscopic Josephson junctions are considered in the presence of a dc voltage bias ${\mathit{V}}_{0}$ and of nonclassical electromagnetic fields. It is shown that when the voltage ${\mathit{V}}_{0}$ is an integer multiple of a certain value, the current through the junction has a dc component. This is broadly similar to Shapiro steps in macroscopic Josephson junctions, but the details depend on the nature of the nonclassical electromagnetic field. Coherent states, squeezed states, and number eigenstates are considered and the corresponding Shapiro steps are studied in detail. The presence of thermal noise in the nonclassical fields is also considered and its effect on the results is studied.

Physical review. B, Condensed matter•May 1, 1994•120 citations

CORRELATION OF SUPERCURRENTS IN TWO DISTANT MESOSCOPIC SQUID RINGS IN THE PRESENCE OF TWO-MODE NONCLASSICAL FIELD

Zhihong Peng, Jian Zou, Bin Shao +1 more

In this paper we consider two distant mesoscopic superconducting quantum interference device (SQUID) rings A and B in the presence of two-mode squeezed vacuum state field, and aim to see the effect of the field on the correlation of supercurrents in the two rings. We know the degree of entanglement of the two-mode squeezed vacuum state increases with the squeezing parameter r. In this paper we find that the correlation of the supercurrents increases with the parameter r too, meaning that the correlation of the supercurrents increases with the degree of entanglement of the field.

International Journal of Modern Physics B•Apr 30, 2005•1 citation

Continuous–Variable Entanglement in a Coupled Field–Mesoscopic Josephson Junction System

Tian-Hai Zeng, Shao Bin, Chang Ping +1 more

Continuous–variable entanglement in the interacting system of a mesoscopic Josephson junction with a squeezed field is investigated. It is shown that when the cavity field is initially prepared in a squeezed vacuum state and the junction in its lowest energy state, the coupling system can evolve into a two-mode Gaussian state. The time-dependent characteristic function in the Wigner representation for the system is analytically obtained, and the squeezing degree of the initial cavity field turns out to have not only an apparent enhancing but also a weakening effect on the entanglement of the coupling system under suitable parameter conditions.

Chinese Physics Letters•Sep 27, 2006•6 citations
Higher-order squeezing degree in mesoscopic Josephson junction of a circular superconducting ring can be improved if the electromagnetic field is initially in a successive squeezed vacuum state. We compare our method with the usual procedure for higher-order squeezing and consider the effect of different small inductances on the 2Nth-order squeezing degree for quantum current.
Signal-to-quantum noise ratio for quantum current in mesoscopic Josephson junction of a circular superconducting ring can be improved if the electromagnetic field is in a successive squeezed coherent state. The mesoscopic Josephson junctions can feel the difference between the successive squeezed coherent states and other types of squeezed coherent states because their current–voltage Shapiro steps are different. We compare our method with another procedure for superposition of two squeezed coherent states (a squeezed even coherent state) and consider the effect of different large inductances on the supercurrent.
Circular superconducting devices with mesoscopic Josephson junctions are considered in the presence of a dc voltage bias V0{\mathit{V}}_{0}V0​ and of nonclassical electromagnetic fields. It is shown that when the voltage V0{\mathit{V}}_{0}V0​ is an integer multiple of a certain value, the current through the junction has a dc component. This is broadly similar to Shapiro steps in macroscopic Josephson junctions, but the details depend on the nature of the nonclassical electromagnetic field. Coherent states, squeezed states, and number eigenstates are considered and the corresponding Shapiro steps are studied in detail. The presence of thermal noise in the nonclassical fields is also considered and its effect on the results is studied.
In this paper we consider two distant mesoscopic superconducting quantum interference device (SQUID) rings A and B in the presence of two-mode squeezed vacuum state field, and aim to see the effect of the field on the correlation of supercurrents in the two rings. We know the degree of entanglement of the two-mode squeezed vacuum state increases with the squeezing parameter r. In this paper we find that the correlation of the supercurrents increases with the parameter r too, meaning that the correlation of the supercurrents increases with the degree of entanglement of the field.
Continuous–variable entanglement in the interacting system of a mesoscopic Josephson junction with a squeezed field is investigated. It is shown that when the cavity field is initially prepared in a squeezed vacuum state and the junction in its lowest energy state, the coupling system can evolve into a two-mode Gaussian state. The time-dependent characteristic function in the Wigner representation for the system is analytically obtained, and the squeezing degree of the initial cavity field turns out to have not only an apparent enhancing but also a weakening effect on the entanglement of the coupling system under suitable parameter conditions.