Tuning locality of pair coherence in graphene-based Andreev interferometers.
We report on gate-tuned locality of superconductivity-induced phase-coherent magnetoconductance oscillations in a graphene-based Andreev interferometer, consisting of a T-shaped graphene bar in contact with a superconducting Al loop. The conductance oscillations arose from the flux change through the superconducting Al loop, with gate-dependent Fraunhofer-type modulation of the envelope. We confirm a transitional change in the character of the pair coherence, between local and nonlocal, in the same device as the effective length-to-width ratio of the device was modulated by tuning the pair-coherence length ξT in the graphene layer.
Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Minsoo
M
Kim
Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Dongchan
D
Jeong
Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Gil-Ho
GH
Lee
Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Yun-Sok
YS
Shin
Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Hyun-Woo
HW
Lee
Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Hu-Jong
HJ
Lee