0−π transitions in a Josephson junction of an irradiated Weyl semimetal

Abstract

We propose a setup for the experimental realization of anisotropic 0-π transitions of the Josephson current, in a junction whose link is made of irradiated Weyl semi-metal (WSM), due to the presence of chiral nodes. The Josephson current through a time-reversal symmetric WSM has anisotropic (with respect to the orientation of the chiral nodes) periodic oscillations as a function of k0L, where k0 is the (relevant) separation of the chiral nodes and L is the length of the sample. We then show that the effective value of k0 can be tuned with precision by irradiating the sample with linearly polarized light, which does not break time-reversal invariance, resulting in 0-π transitions of the critical current. We also discuss the feasibility and robustness of our setup.

Chirality blockade of Andreev reflection in a magnetic Weyl semimetal

“…We also discuss the subtle role played by inversion symmetry by contrasting a scalar with a pseudoscalar pair potential [10]. The absence of the chirality blockade for pseudoscalar pairing explains why it did not appear in the many previous studies of Andreev reflection in a Weyl semimetal [11][12][13][14][15][16][17][18][19].…”

Transport through Andreev bound states in a Weyl semimetal quantum dot

“…Their values can be determined from the band structure of the system and the bias V 0 present in the dot. At small enough bias, the periodicity reduces to the expected 2k 0 L = nπ oscillations 21,31 . Model and setup.-The simplest model of a WSM with broken time-reversal (TR) symmetry requires two chiral nodes in momentum space, whereas the simplest WSM with broken inversion symmetry requires the presence of four chiral nodes.…”

“…A quantum dot made of WSM material in the presence of superconductors is of particular interest due to the distinctive nature of transport at a WSM-Superconductor (SC) interface 13,21,[30][31][32] and provides the possibility of capturing the otherwise elusive physics associated with the chiral excitation in the WSM 30 . In this manuscript we study transport through the Andreev states of a WSM quantum dot in a simple setup where we sandwich the dot in between a superconductor and a normal lead (see Fig.…”

Photoinduced interfacial chiral modes in threefold topological semimetal

“…Apart from these, optical pumping can also be used to control the spin and the valley degree of freedom in Dirac materials [19][20][21][22], which is the key requirement for the spin and valleytronics. Moreover, electromagnetic field can play the key role in 0 − π phase transition in Josephson current in a normal-superconductor-normal (NSN) hybrid junction made of silicene [23] and Weyl semimetal [24].…”