Abstract

We investigate the nonequilibrium populations of Andreev bound states (ABSs) in ballistic graphene three-terminal Josephson junctions (JJs). Our measurements reveal periodic resistance oscillations as a function of the superconducting phase, which is modulated by the applied magnetic flux. Additionally, we observe several voltage-induced crossovers, where resistance oscillations alternate between minima and maxima at integer flux quanta, corresponding to 0 and π phase shifts, respectively. We utilize a microscopic model for long ballistic Andreev interferometers, accounting for both perturbative and non-perturbative scattering processes. This model attributes the 0−π crossovers to phase-sensitive Andreev reflections (ARs), which convert normal current into ABSs with nonequilibrium populations. Our combined theoretical and experimental approach suggests that unconventional energy-phase relations, such as π-shifted ABSs, can be created in multiterminal JJs without relying on complex Cooper quartet or Floquet physics.

Abstract

We investigate the nonequilibrium populations of Andreev bound states (ABSs) in ballistic graphene three-terminal Josephson junctions (JJs). Our measurements reveal periodic resistance oscillations as a function of the superconducting phase, which is modulated by the applied magnetic flux. Additionally, we observe several voltage-induced crossovers, where resistance oscillations alternate between minima and maxima at integer flux quanta, corresponding to 0 and π phase shifts, respectively. We utilize a microscopic model for long ballistic Andreev interferometers, accounting for both perturbative and non-perturbative scattering processes. This model attributes the 0−π crossovers to phase-sensitive Andreev reflections (ARs), which convert normal current into ABSs with nonequilibrium populations. Our combined theoretical and experimental approach suggests that unconventional energy-phase relations, such as π-shifted ABSs, can be created in multiterminal JJs without relying on complex Cooper quartet or Floquet physics.

Abstract

We investigate the nonequilibrium populations of Andreev bound states (ABSs) in ballistic graphene three-terminal Josephson junctions (JJs). Our measurements reveal periodic resistance oscillations as a function of the superconducting phase, which is modulated by the applied magnetic flux. Additionally, we observe several voltage-induced crossovers, where resistance oscillations alternate between minima and maxima at integer flux quanta, corresponding to 0 and π phase shifts, respectively. We utilize a microscopic model for long ballistic Andreev interferometers, accounting for both perturbative and non-perturbative scattering processes. This model attributes the 0−π crossovers to phase-sensitive Andreev reflections (ARs), which convert normal current into ABSs with nonequilibrium populations. Our combined theoretical and experimental approach suggests that unconventional energy-phase relations, such as π-shifted ABSs, can be created in multiterminal JJs without relying on complex Cooper quartet or Floquet physics.

Abstract

We investigate the nonequilibrium populations of Andreev bound states (ABSs) in ballistic graphene three-terminal Josephson junctions (JJs). Our measurements reveal periodic resistance oscillations as a function of the superconducting phase, which is modulated by the applied magnetic flux. Additionally, we observe several voltage-induced crossovers, where resistance oscillations alternate between minima and maxima at integer flux quanta, corresponding to 0 and π phase shifts, respectively. We utilize a microscopic model for long ballistic Andreev interferometers, accounting for both perturbative and non-perturbative scattering processes. This model attributes the 0−π crossovers to phase-sensitive Andreev reflections (ARs), which convert normal current into ABSs with nonequilibrium populations. Our combined theoretical and experimental approach suggests that unconventional energy-phase relations, such as π-shifted ABSs, can be created in multiterminal JJs without relying on complex Cooper quartet or Floquet physics.