(Invited) Hybrid Nb-In0.75Ga0.25As quantum wells circuits for scalable quantum computing

Kaveh Delfanazari

Published Nov 1, 2017• 0 citations

Abstract

We experimentally demonstrate an on-chip hybrid S-Sm circuit consisting of eight Nb-In0.75Ga0.25As quantum wells-Nb ballistic Josephson junctions.

Related papers

Research data supporting "On-chip hybrid Superconducting-Semiconducting Circuit for Scalable Quantum Computing"

Kaveh Delfanazari, Reuben K. Puddy, Pengfei Ma +8 more

In this paper, we experimentally demonstrate a hybrid superconducting-semiconducting (S-Sm) circuit consisting of eight planar and ballistic Nb-In0.75Ga0.25As-Nb Josephson junctions.

Nov 9, 20190 citations

On-chip hybrid Superconducting-Semiconducting Circuit

Kaveh Delfanazari, Reuben K. Puddy, Ma, P +8 more

In this paper, we experimentally demonstrate a hybrid superconducting-semiconducting (S-Sm) circuit consisting of eight planar and ballistic Nb-In0.75Ga0.25As-Nb Josephson junctions. E-beam lithography was used to fabricate the Josephson junctions on an InGaAs chip. In contrast to our previous studies on long junctions that were fabricated by photolithography, in this study, we observe the induced superconductivity in an In0.75Ga0.25As quantum well at higher temperatures, between T= 0.3 and 1.4 K (3He cryostat temperature range). The induced superconducting gap of & #x0394;ind= 0.65 meV was measured at lowest base temperature T= 300 mK. The effect of temperature and magnetic fields B on the induced superconductivity are presented. Our results suggest that our In0.75Ga0.25As heterojunctions is a promising scalable material system for quantum processing and computing applications.

Mar 6, 20180 citations

On-chip Hybrid Superconducting-Semiconducting Quantum Circuit

Kaveh Delfanazari, Michael Joseph Kelly, Charles G. Smith +8 more

In this paper, we experimentally demonstrate a hybrid superconducting-semiconducting circuit consisting of eight planar and ballistic Nb-In0.75Ga0.25As-Nb Josephson junctions. E-beam lithography was used to fabricate the Josephson junctions on an InGaAs chip. In contrast to our previous studies on long junctions that were fabricated by photolithography, in this study, we observe the induced superconductivity in an In0.75Ga0.25As quantum well at higher temperatures, between T = 0.3 and 1 K (3He cryostat temperature range). The induced superconducting gap of Δind= 0.65 meV was measured at lowest base temperature T = 300 mK. The effect of temperature and magnetic fields B on the induced superconductivity are presented. Our results suggest that our In0.75Ga0.25As heterostructure is a promising scalable material system for quantum processing and computing applications.

IEEE Transactions on Applied SuperconductivityMar 6, 201818 citations

Unconventional Josephson effect in two dimensional electron gas-based superconductor-semiconductor Josephson junctions

Kaveh Delfanazari, Peng‐Cheng Ma, Ian A. Farrer +4 more

Further to the development of scalable hybrid quantum circuits introduced by us [1-5], here we report on the discovery of an unconventional Josephson effect in hybrid In0.75Ga0.25As two-dimensional electron gas-Nb junctions that are designed and fabricated for scalable hybrid quantum circuit integration. Reference: [1] K. Delfanazari, et al, Adv. Mater. 29, 1701836 (2017). [2] K. Delfanazari, et al, J. Magn. Magn. Mater. 459, 282-284 (2018). [3] K. Delfanazari, et al, IEEE Trans. Appl. Supercond. 28, 1100304 (2018).

Oct 5, 20180 citations

Coherent quantum transport in hybrid Nb-InGaAs-Nb Josephson junctions

Kaveh Delfanazari, Reuben K. Puddy, Pengfei Ma +8 more

Bulletin of the American Physical SocietyMar 14, 20170 citations

(invited) Quantum integrated circuits based on superconducting two-dimensional electron gas platform

Kaveh Delfanazari, Pengfei Ma, Ian A. Farrer +4 more

...we introduced an integrated circuit consisting of arrays of planar Josephson junctions based on two-dimensional electron gas (2DEG) in In0.75Ga0.25As heterostructure. The methods that are used for ballistic 2D Josephson junction and hybrid quantum integrated circuit fabrication will be demonstrated. Furthermore, the temperature and magnetic field dependencies of the phase coherent quantum transport in 2D Josephson junctions, the induced superconducting properties into 2DEG, and the subharmonic energy gap structures (SGS) due to Andreev reflections at the S-Sm interfaces will be discussed. Reference: [1] K. Delfanazari, et al, Adv. Mater. 29, 1701836 (2017). [2] K. Delfanazari, et al, J. Magn. Magn. Mater. 459, 282-284 (2018). [3] K. Delfanazari, et al, IEEE Trans. Appl. Supercond. 28, 1100304 (2018).

Dec 1, 20180 citations