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

arXiv:cond-mat/0008023

THE ZENO EFFECT AND AN INTER-LAYER PAIRING MECHANISM FOR HIGH-TEMPERATURE SUPERCONDUCTIVITY IN LAYERED MATERIALS

Nitesh Kumar

Published May 1, 2001• 1 citation
arXivHTMLPDF

Abstract

Quantum Zeno Effect (QZE) is the suppression of the inter-subspace transition by a relatively fast intra-subspace decoherence. Earlier, we had proposed a QZE-based mechanism for the temperature-dependent normal-state c-axis resistivity of the layered high-T$_c$ cuprate superconductors in which the single-particle inter-layer tunneling is blocked by the strong intra-layer decoherence (entanglement). We now argue that while the single-particle inter-layer tunneling is thus blocked, the tunneling of the bosonic BCS-like pairs must remain unblocked inasmuch as a BCS pairing condensate is an eigenstate of the pair annihilation operator. This pair tunneling stabilizes

DOI
10.1142/9789812811523_0004

Related papers

Zeno blocking of interplanar tunneling by intraplane inelastic scattering in layered superconductors: A generalized spin-boson analysis

Manoranjan Kumar, Sushanta Dattagupta, Narendra Kumar

Following an earlier proposal that the observed temperature dependence of the normal-state c-axis resistivity of oxide superconductors can be understood as arising from the inhibition of electron transport along the c axis due to in-plane incoherent inelastic scatterings suffered by the tagged electron, we consider a specific form for the interaction Hamiltonian. In this, the tagged electron is coupled to bosonic baths at adjacent planes (the baths at any two planes being uncorrelated) and is coupled also to the intraplane momentum-flip degree of freedom via the bath degrees of freedom. Thus our model Hamiltonian incorporates the earlier proposed picture that each in-plane inelastic scattering event is like a measurement of which plane the electron is in, and this, as in the quantum Zeno effect, leads to the suppression of interplane tunneling. In the present scenario it is the baths which bring about a coupling between the intraplane and interplane degrees of freedom. For simplicity we confine ourselves to dynamics in two adjacent planes and allow for two states only, as far as momentum flips due to scattering are concerned. In the case when the intraplane dynamics is absent, our model reduces effectively to the usual spin-boson model. We solve for the reduced tunneling dynamics of the electron using a non-Markovian master equation approach. Our numerical results on the survival probability of the electron in the initial plane show that the intraplane momentum flips lead to further inhibition of the interplane tunneling over and above the inhibition effected by pure spin-boson dynamics.

Physical review. B, Condensed matter•Mar 19, 2002•4 citations

Blocking of inter-subspace tunneling by intra subspace inelastic scattering

T. P. Pareek, A. M. Jayannavar, Naveen Kumar

In recent years the notion of intrinsic decoherence and dephasing of a particle interacting with its environment is being investigated intensively. This has an important bearing on a plausible causal connection between incoherent c-axis resistivity and high-temperature superconductivity. In our work we study the tunnel supression and incoherent motion of a particle tunneling between two sites. The bosonic excitations of the environment are coupled to only one site inducing on-site spin flips. We show that this on-site spin flip scattering makes the tunnel motion incoherent. In the high-temperature limit incoherent rate or hopping rate has been calculated. We also briefly discuss the renormalization of the effective tunneling by environmental coupling at zero temperature following Wegner's renormalization group procedure.

arXiv:cond-mat/9811368•Nov 26, 1998•0 citations

BOSE-EINSTEIN CONDENSATION IN QUASI-2D SYSTEMS: APPLICATIONS TO HIGH- T c SUPERCONDUCTIVITY

Carlos Villarreal, MANUEL DE LLANO

We describe high-Tc superconductivity in layered materials within a BCS theory as a BEC of massless-like Cooper pairons satisfying a linear dispersion relation, and propagating within quasi-2D layers of finite width defined by the charge distribution about the CuO_2 planes. We obtain a closed formula for the critical temperature, Tc, that depends on the layer width, the binding energy of Cooper's pairs, and the average in-plane penetration depth. This formula reasonably reproduces empirical values of superconducting transition temperatures for several different cuprate materials near the optimal doping regime, as well as for YBCO films with different doping degrees.

arXiv:0905.1535•Workshop on Quantum Field Theory Under the Influence of External Conditions (QFEXT)•May 1, 2010•1 citation

Optimal interlayer hopping and high temperature Bose–Einstein condensation of local pairs in quasi 2D superconductors

P E Kornilovitch, J. P. Hague

Both FeSe and cuprate superconductors are quasi 2D materials with high transition temperatures and local fermion pairs. Motivated by such systems, we investigate real space pairing of fermions in an anisotropic lattice model with intersite attraction, V, and strong local Coulomb repulsion, U, leading to a determination of the optimal conditions for superconductivity from Bose-Einstein condensation. Our aim is to gain insight as to why high temperature superconductors tend to be quasi 2D. We make both analytically and numerically exact solutions for two body local pairing applicable to intermediate and strong V. We find that the Bose-Einstein condensation temperature of such local pairs pairs is maximal when hopping between layers is intermediate relative to in-plane hopping, indicating that the quasi 2D nature of unconventional superconductors has an important contribution to their high transition temperatures.

arXiv:1407.3040•Journal of Physics Condensed Matter•Jan 28, 2015•7 citations

Generalized Dynamical Decoupling from the Quantum Zeno Effect

Paolo Facchi A, Daniel A. Lidar, Saverio Pascazio

We unify the quantum Zeno effect (QZE) and "bang-bang" (BB) decoupling, recently introduced as a method for suppressing decoherence in open quantum systems: in both cases strong coupling to an external system or apparatus induces a dynamical superselection rule that partitions the open system's Hilbert space into quantum Zeno subspaces. Our unification makes use of von Neumann's ergodic theorem and avoids making any of the symmetry assumptions usually made in discussions of BB. Thus we are able to generalize BB to arbitrary fast and strong pulse sequences, requiring no symmetry. We further point out that the inverse QZE implies that BB can in some cases accelerate, rather than inhibit, decoherence.

•Mar 20, 2003•2 citations

Optimal interlayer hopping and high temperature Bose–Einstein condensation of local pairs in quasi 2D superconductors

Kornilovitch, P. E., Hague, J. P.

Both FeSe and cuprate superconductors are quasi 2D materials with high transition temperatures and local fermion pairs. Motivated by such systems, we investigate real space pairing of fermions in an anisotropic lattice model with intersite attraction, V, and strong local Coulomb repulsion, U, leading to a determination of the optimal conditions for superconductivity from Bose–Einstein condensation. Our aim is to gain insight as to why high temperature superconductors tend to be quasi 2D. We make both analytically and numerically exact solutions for two body local pairing applicable to intermediate and strong V. We find that the Bose–Einstein condensation temperature of such local pairs pairs is maximal when hopping between layers is intermediate relative to in-plane hopping, indicating that the quasi 2D nature of unconventional superconductors has an important contribution to their high transition temperatures.

•Jan 28, 2015•6 citations
Quantum Zeno Effect (QZE) is the suppression of the inter-subspace transition by a relatively fast intra-subspace decoherence. Earlier, we had proposed a QZE-based mechanism for the temperature-dependent normal-state c-axis resistivity of the layered high-Tc_cc​ cuprate superconductors in which the single-particle inter-layer tunneling is blocked by the strong intra-layer decoherence (entanglement). We now argue that while the single-particle inter-layer tunneling is thus blocked, the tunneling of the bosonic BCS-like pairs must remain unblocked inasmuch as a BCS pairing condensate is an eigenstate of the pair annihilation operator. This pair tunneling stabilizes
Following an earlier proposal that the observed temperature dependence of the normal-state c-axis resistivity of oxide superconductors can be understood as arising from the inhibition of electron transport along the c axis due to in-plane incoherent inelastic scatterings suffered by the tagged electron, we consider a specific form for the interaction Hamiltonian. In this, the tagged electron is coupled to bosonic baths at adjacent planes (the baths at any two planes being uncorrelated) and is coupled also to the intraplane momentum-flip degree of freedom via the bath degrees of freedom. Thus our model Hamiltonian incorporates the earlier proposed picture that each in-plane inelastic scattering event is like a measurement of which plane the electron is in, and this, as in the quantum Zeno effect, leads to the suppression of interplane tunneling. In the present scenario it is the baths which bring about a coupling between the intraplane and interplane degrees of freedom. For simplicity we confine ourselves to dynamics in two adjacent planes and allow for two states only, as far as momentum flips due to scattering are concerned. In the case when the intraplane dynamics is absent, our model reduces effectively to the usual spin-boson model. We solve for the reduced tunneling dynamics of the electron using a non-Markovian master equation approach. Our numerical results on the survival probability of the electron in the initial plane show that the intraplane momentum flips lead to further inhibition of the interplane tunneling over and above the inhibition effected by pure spin-boson dynamics.
In recent years the notion of intrinsic decoherence and dephasing of a particle interacting with its environment is being investigated intensively. This has an important bearing on a plausible causal connection between incoherent c-axis resistivity and high-temperature superconductivity. In our work we study the tunnel supression and incoherent motion of a particle tunneling between two sites. The bosonic excitations of the environment are coupled to only one site inducing on-site spin flips. We show that this on-site spin flip scattering makes the tunnel motion incoherent. In the high-temperature limit incoherent rate or hopping rate has been calculated. We also briefly discuss the renormalization of the effective tunneling by environmental coupling at zero temperature following Wegner's renormalization group procedure.
We describe high-Tc superconductivity in layered materials within a BCS theory as a BEC of massless-like Cooper pairons satisfying a linear dispersion relation, and propagating within quasi-2D layers of finite width defined by the charge distribution about the CuO_2 planes. We obtain a closed formula for the critical temperature, Tc, that depends on the layer width, the binding energy of Cooper's pairs, and the average in-plane penetration depth. This formula reasonably reproduces empirical values of superconducting transition temperatures for several different cuprate materials near the optimal doping regime, as well as for YBCO films with different doping degrees.
Both FeSe and cuprate superconductors are quasi 2D materials with high transition temperatures and local fermion pairs. Motivated by such systems, we investigate real space pairing of fermions in an anisotropic lattice model with intersite attraction, V, and strong local Coulomb repulsion, U, leading to a determination of the optimal conditions for superconductivity from Bose-Einstein condensation. Our aim is to gain insight as to why high temperature superconductors tend to be quasi 2D. We make both analytically and numerically exact solutions for two body local pairing applicable to intermediate and strong V. We find that the Bose-Einstein condensation temperature of such local pairs pairs is maximal when hopping between layers is intermediate relative to in-plane hopping, indicating that the quasi 2D nature of unconventional superconductors has an important contribution to their high transition temperatures.
We unify the quantum Zeno effect (QZE) and "bang-bang" (BB) decoupling, recently introduced as a method for suppressing decoherence in open quantum systems: in both cases strong coupling to an external system or apparatus induces a dynamical superselection rule that partitions the open system's Hilbert space into quantum Zeno subspaces. Our unification makes use of von Neumann's ergodic theorem and avoids making any of the symmetry assumptions usually made in discussions of BB. Thus we are able to generalize BB to arbitrary fast and strong pulse sequences, requiring no symmetry. We further point out that the inverse QZE implies that BB can in some cases accelerate, rather than inhibit, decoherence.
Both FeSe and cuprate superconductors are quasi 2D materials with high transition temperatures and local fermion pairs. Motivated by such systems, we investigate real space pairing of fermions in an anisotropic lattice model with intersite attraction, V, and strong local Coulomb repulsion, U, leading to a determination of the optimal conditions for superconductivity from Bose–Einstein condensation. Our aim is to gain insight as to why high temperature superconductors tend to be quasi 2D. We make both analytically and numerically exact solutions for two body local pairing applicable to intermediate and strong V. We find that the Bose–Einstein condensation temperature of such local pairs pairs is maximal when hopping between layers is intermediate relative to in-plane hopping, indicating that the quasi 2D nature of unconventional superconductors has an important contribution to their high transition temperatures.