Campus de Excelencia InterncionalCampus of International Excellence

Tunable proximity effect in cuprate superconductor/graphene junctions

Fechas celebración

Desde el 24-05-2018 hasta el 24-05-2018

Hora Celebración

12:00 h.

Lugar de Celebración

Dpto. Física de la Materia Condensada, Facultad Ciencias, Modulo 3 Sala de Seminarios (5ª Planta)

Descripción

Presentación a cargo de David Perconte-Duplain

(Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay)

Abstract:  

Superconductivity induced by proximity effect is particularly interesting in graphene. For example, because of the conduction and valence bands touching at the Dirac point, an unusual form of the Andreev reflection (the so-called specular Andreev reflection) has been predicted theoretically to happen at a superconductor/graphene interface [1]. We have fabricated cuprate superconductor/graphene planar junctions using a combination of lithography, ion irradiation and CVD graphene transfer techniques. The conductance measurements show that the interfaces are transparent such that the electrical transport is governed by Andreev reflection. The devices allow the modulation of graphene doping via either a top or a back gate, and thus enable electrical control of the graphene’s Fermi energy. This allows us to evidence superconducting electron interference effects that constitute an analogue of Klein tunneling for superconducting pairs. The interference effects periodically modulate the conductance across the junction. We perform numerical simulations based on the model developed in [2]. We compare this simulated superconductor graphene interface conductance to the experimental conductance. We will also present recent work on nanometric cuprate superconductor/graphene junctions where we observe conductance oscillations with bias voltage. These oscillation period decrease when increasing the graphene channel length which indicates that the interferences happen inside the graphene channel.

cid:E16283C1-AF0D-418F-BA2D-F78A1BBB365A

References:

[1] C. W. J. Beenakker, Phys. Rev. Lett. 97, 067007 (2007)

[2] J. Linder, A. Sudbo, Phys. Rev. Lett. 99, 147001 (2007)

 

Más información: http://www.ifimac.uam.es/category/seminars/

 

Dear all:

 

A new IFIMAC Conference will  take place on Thursday; May 24th at the  Condensed Matter Physics Center (IFIMAC )

You will find all the information below.

 

WHEN: Thursday; May 24 th (2018); 12.00 h

WHERE: Dpto. Física de la Materia Condensada, Facultad Ciencias, Module 3, Seminar Room (5th Floor)

 

SPEAKER: David Perconte-Duplain (Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay)

 

TITLE: Tunable proximity effect in cuprate superconductor/graphene junctions

 

ABSTRACT:

Superconductivity induced by proximity effect is particularly interesting in graphene. For example, because of the conduction and valence bands touching at the Dirac point, an unusual form of the Andreev reflection (the so-called specular Andreev reflection) has been predicted theoretically to happen at a superconductor/graphene interface [1]. We have fabricated cuprate superconductor/graphene planar junctions using a combination of lithography, ion irradiation and CVD graphene transfer techniques. The conductance measurements show that the interfaces are transparent such that the electrical transport is governed by Andreev reflection. The devices allow the modulation of graphene doping via either a top or a back gate, and thus enable electrical control of the graphene’s Fermi energy. This allows us to evidence superconducting electron interference effects that constitute an analogue of Klein tunneling for superconducting pairs. The interference effects periodically modulate the conductance across the junction. We perform numerical simulations based on the model developed in [2]. We compare this simulated superconductor graphene interface conductance to the experimental conductance. We will also present recent work on nanometric cuprate superconductor/graphene junctions where we observe conductance oscillations with bias voltage. These oscillation period decrease when increasing the graphene channel length which indicates that the interferences happen inside the graphene channel.

References:

[1] C. W. J. Beenakker, Phys. Rev. Lett. 97, 067007 (2007)

[2] J. Linder, A. Sudbo, Phys. Rev. Lett. 99, 147001 (2007)

 

 

More information: http://www.ifimac.uam.es/category/seminars/

Agentes y colaboradores

  • Universidad Autónoma de Madrid
  • CSIC
  • ASEYACOVI
  • ACENOMA
  • AICA
  • Centro de Microanálisis de Materiales (CMAM)
  • Centro de Investigación en Física de la Materia Condensada (IFIMAC)
  • CBMSO - Centro de Biología Molecular Severo Ochoa
  • CIAL - Centro de Investigación en Ciencias de la Alimentación
  • CNB - Centro Nacional de Biotecnología 
  • Centro de Iniciativas Emprendedoras (CIADE)
  • Cámara de Madrid
  • FEMAN
  • Fundación Universitaria Autónoma de Madrid
  • ICMAT - Instituto de Ciencias Matemáticas
  • ICMM - Instituto de Ciencia de Materiales de Madrid
  • ICP - Instituto de Catálisis y Petroquímica
  • ICV - Instituto de Cerámica y Vidrio
  • IFT - Instituto de FísicaTeórica
  • IIBM - Instituto de Investigaciones Biomédicas Alberto Sols
  • IMDEA - Alimentación
  • IMDEA - Nanociencia
  • IMM - Instituto de Microelectrónica de Madrid
  • InNorMadrid
  • Parque Científico de Madrid
  • Oficina de Transferencia de Resultados de la Investigación (OTRI) de la UAM
  • Facultad de Ciencias
  • Facultad de Ciencias Económicas y Empresariales
  • Facultad de Derecho
  • Facultad de Filosofía y Letras
  • Facultad de Medicina
  • Facultad de Formación de Profesorado y Educación
  • Facultad de Psicología
  • Escuela Politécnica Superior
Proyecto realizado con ayudas concedidas por el Ministerio de Economía y Competitividad / EXPEDIENTE: CEI10-1-0009 CEI UAM+CSIC: INNOCAMPUS 2010 Proyecto financiado por el Ministerio de Educación, Cultura y Deporte, y el Ministerio de Economía y Competitividad en el marco del Programa Campus de Excelencia Internacional/ EXPEDIENTE: CEI10-1-0009 CEI UAM+CSIC: INNOCAMPUS 2010