邓昊

Two-dimensional electron system (2DES)

2DES is a research field in condensed matter physics with long history. Under the magnetic field, the continuous density of states of a 2DES is quantized into discrete energy levels called Landau levels (LLs). Depending on the filling factor which is the amount of filled LLs under the Fermi energy, the 2DES shows rich phases at low temperature. Following the discovery of the integer quantum Hall effect (IQHE), fractional quantum Hall effect, magnetic-field-induced quantum Wigner crystal, composite fermion, striped/nematic phase, skyrmion, etc., have been observed/confirmed by experiments successively. Besides the IQHE which could be explained by a single-electron picture, most of the exotic phases of 2DES have many-body origin. The studies on those many-body phases of 2DES not only help us to understand the physics of highly correlated system, but also unveil the potential, impactful applications such as quantum computing (QC).

Circuit quantum electrodynamics (cQED)

cQED is one of the most active research fields because of its application in QC as the superconducting (SC) quantum circuit. In this approach of QC, the “artificial atom” is constructed by adding the nonlinear Josephson junction to the carefully-designed, low-loss, linear circuits made by superconductor. Thanks to the nonlinearity, (usually the lowest) two energy levels could be selected out as the qubit for the purpose of QC. Because of the fully artificial construction and highly controllable behavior, the cQED system is one of the most competitive platforms of QC, showing the advantages in flexibility, operation, readout, and scaling up. However, the advantages of cQED system are also accompanied by challenges: the strong coupling to the environment makes cQED system susceptible to the noise and interference. Both the advantages and challenges indicate that, there is grand space to explore in the cQED system.

R. Gao, F. Wu, H. Sun, J. Chen, H. Deng, X. Ma, X. Miao, Z, Song, X. Wan, F. Wang, T. Via, M. Ying, C. Zhang, Y. Shi, H. Zhao, C. Deng, The Effects of Disorder in Superconducting Materials on Qubit Coherence, Nat. Commun. 16, 3620 (2025)

F. Wang, K. Lu, H. Zhan, L. Ma, F. Wu, H. Sun, H. Deng, Y. Bai, F. Bao, X. Chang, R. Gao, X. Gao, G. Gong, L. Hu, R. Hu, H. Ji, X. Ma, L. Mao, Z. Song, C. Tang, H. Wang, T. Wang, Z. Wang, T. Xia, H. Xu, Z. Zhan, G. Zhang, T. Zhou, M. Zhu, Q. Zhu, S. Zhu, X. Zhu, Y. Shi, H. Zhao, Hui-Hai, C. Deng, High-coherence Fluxonium Qubits Manufactured with a Wafer-scale-uniformity Process, Phys. Rev. Appl. 23, 044064 (2025)

T. Wang, F. Wu, F. Wang, X. Ma, G. Zhang, J. Chen, H. Deng, R. Gao, R. Hu, L. Ma, Z. Song, T. Xia, M. Ying, H. Zhan, H. Zhao, C. Deng, Efficient Initialization of Fluxonium Qubits based on Auxiliary Energy Levels, Phys. Rev. Lett. 132, 230601 (2024)

X. Ma, G. Zhang, F. Wu, F. Bao, X. Chang, J. Chen, H. Deng, R. Gao, X. Gao, L. Hu, H. Ji, H. Ku, K. Lu, L. Ma, L. Mao, Z. Song, H. Sun, C. Tang, F. Wang, H. Wang, T. Wang, T. Xia, M. Ying, H. Zhan, T. Zhou, M. Zhu, Q. Zhu, Y. Shi, H. Zhao, C. Deng, Native Approach to Controlled-Z Gates in Inductively Coupled Fluxonium Qubits, Phys. Rev. Lett. 132, 060602 (2024)

H. Deng, Z. Song, R. Gao, T. Xia, F. Bao, X. Jiang, H. Ku, Z. Li, X. Ma, J. Qin, H. Sun, C. Tang, T. Wang, F. Wu, W. Yu, G. Zhang, X. Zhang, J. Zhou, X. Zhu, Y. Shi, H. Zhao, C. Deng, Titanium Nitride Film on Sapphire Substrate with Low Dielectric Loss for Superconducting Qubits, Phys. Rev. Appl. 19, 024013 (2023)

R. Gao, H. Ku, H. Deng, W. Yu, T. Xia, F. Wu, Z. Song, M. Wang, X. Miao, C. Zhang, Y. Lin, Y. Shi, H. Zhao, C.

Deng, Ultrahigh Kinetic Inductance Superconducting Materials from Spinodal Decomposition, Advanced Materials 34, 2201268 (2022)

F. Bao, H. Deng, D. Ding, R. Gao, X. Gao, C. Huang, X. Jiang, H. Ku, Z. Li, X. Ma, X. Ni, J. Qin, Z. Song, H. Sun, C. Tang, T. Wang, F. Wu, T. Xia, W. Yu, F. Zhang, G. Zhang, X. Zhang, J. Zhou, X. Zhu, Y. Shi, J. Chen, H. Zhao, C. Deng, Fluxonium: An Alternative Qubit Platform for High-Fidelity Operations, Phys. Rev. Lett. 129, 010502 (2022)

*Selected as Editor Suggestion

R. Gao, W. Yu, H. Deng, H. Ku, Z. Li, M. Wang, X. Miao, Y. Lin, C. Deng, Epitaxial titanium nitride microwave resonators: Structural, chemical, electrical, and microwave properties, Phys. Rev. Materials 6, 036202 (2022)

K. Villegas Rosales, S. Singh, H. Deng, Y. Chung, L. Pfeiffer, K. West, K. Baldwin, M. Shayegan, Melting phase diagram of bubble phases in high Landau levels, Phys. Rev. B 104, L121110 (2021)

M. Ma, K. Villegas Rosales, H. Deng, Y. Chung, L. Pfeiffer, K. West, K. Baldwin, R. Winkler, M. Shayegan, Thermal and Quantum Melting Phase Diagrams for a Magnetic-Field-Induced Wigner Solid, Phys. Rev. Lett. 125, 036601 (2020)

A. Hatke, H. Deng, Y. Liu, L. Engel, L. Pfeiffer, K. West, K. Baldwin, M. Shayegan, Wigner solid pinning modes tuned by fractional quantum Hall states of a nearby layer, Science Advances 5 (2019)

H. Deng, L. Pfeiffer, K. West, K. Baldwin, L. Engel, M. Shayegan, Probing the Melting of a Two-Dimensional Quantum Wigner Crystal via its Screening Efficiency, Phys. Rev. Lett. 122, 116601 (2019)

*Selected as Editor Suggestion

Y. Chung, K. Villegas Rosales, H. Deng, K. Baldwin, K. West, M. Shayegan, L. Pfeiffer, Multivalley two-dimensional electron system in an AlAs quantum well with mobility exceeding 2×10^6 cm^2 V^-1 s^-1, Phys. Rev. Materials 2, 071001 (2018)

I. Jo, H. Deng, Y. Liu, L. Pfeiffer, K. West, K. Baldwin, M. Shayegan, Cyclotron Orbits of Composite Fermions in the Fractional Quantum Hall Regime, Phys Rev Lett 120, 016802 (2018)

*Selected as Editor Suggestion

H. Deng, L. Engel, L. Pfeiffer, K. West, K. Baldwin, M. Shayegan, Critical filling factor for the formation of a quantum Wigner crystal screened by a nearby layer, Phys. Rev. B 98, 081111 (2018)

M. Ma, M. Hossain, K. Villegas Rosales, H. Deng, T. Tschirky, W. Wegscheider, M. Shayegan, Observation of fractional quantum Hall effect in an InAs quantum well, Phys. Rev. B 96, 241301 (2017)

H. Deng, Y. Liu, I. Jo, L. Pfeiffer, K. West, K. Baldwin, M. Shayegan, Interaction-induced interlayer charge transfer in the extreme quantum limit, Phys. Rev. B 96, 081102 (2017)

H. Deng, Y. Liu, I. Jo, L. Pfeiffer, K. West, K. Baldwin, M. Shayegan, Commensurability Oscillations of Composite Fermions Induced by the Periodic Potential of a Wigner Crystal, Phys. Rev. Lett. 117, 096601 (2016)

*Selected as Editor Suggestion, featured by Physics.

S. Hasdemir, Y. Liu, H. Deng, M. Shayegan, L. Pfeiffer, K. West, K. Baldwin, R. Winkler, ν=1/2 fractional quantum Hall effect in tilted magnetic fields, Phys. Rev. B 91, 045113 (2015)