Li, G. et al. Two-dimensional Fermi surfaces in Kondo insulator SmB6. Science 346, 1208–1212 (2014).

PubMed 
CAS 

Google Scholar
 

Tan, B. S. et al. Unconventional Fermi surface in an insulating state. Science 349, 287–290 (2015).

PubMed 
CAS 

Google Scholar
 

Hartstein, M. et al. Fermi surface in the absence of a Fermi liquid in the Kondo insulator SmB6. Nat. Phys. 14, 166–172 (2018).

CAS 

Google Scholar
 

Liu, H. et al. Fermi surfaces in Kondo insulators. J. Phys. Condens. Matter 30, 16LT01 (2018).

PubMed 

Google Scholar
 

Xiang, Z. et al. Quantum oscillations of electrical resistivity in an insulator. Science 362, 65–69 (2018).

PubMed 
CAS 

Google Scholar
 

Han, Z., Li, T., Zhang, L., Sullivan, G. & Du, R.-R. Anomalous conductance oscillations in the hybridization gap of InAs/GaSb quantum wells. Phys. Rev. Lett. 123, 126803 (2019).

PubMed 
CAS 

Google Scholar
 

Xiao, D., Liu, C.-X., Samarth, N. & Hu, L.-H. Anomalous quantum oscillations of interacting electron-hole gases in inverted type-II InAs/GaSb quantum wells. Phys. Rev. Lett. 122, 186802 (2019).

PubMed 
CAS 

Google Scholar
 

Wang, R., Sedrakyan, T. A., Wang, B., Du, L. & Du, R.-R. Excitonic topological order in imbalanced electron–hole bilayers. Nature 619, 57–62 (2023).

PubMed 
CAS 

Google Scholar
 

Wang, P. et al. Landau quantization and highly mobile fermions in an insulator. Nature 589, 225–229 (2021).

PubMed 
CAS 

Google Scholar
 

Zhu, J., Li, T., Young, A. F., Shan, J. & Mak, K. F. Quantum oscillations in two-dimensional insulators induced by graphite gates. Phys. Rev. Lett. 127, 247702 (2021).

PubMed 
CAS 

Google Scholar
 

Knolle, J. & Cooper, N. R. Quantum oscillations without a Fermi surface and the anomalous de Haas–van Alphen effect. Phys. Rev. Lett. 115, 146401 (2015).

PubMed 

Google Scholar
 

Erten, O., Ghaemi, P. & Coleman, P. Kondo breakdown and quantum oscillations in SmB6. Phys. Rev. Lett. 116, 046403 (2016).

PubMed 

Google Scholar
 

Zhang, L., Song, X.-Y. & Wang, F. Quantum oscillation in narrow-gap topological insulators. Phys. Rev. Lett. 116, 046404 (2016).

PubMed 

Google Scholar
 

Pal, H. K., Piéchon, F., Fuchs, J.-N., Goerbig, M. & Montambaux, G. Chemical potential asymmetry and quantum oscillations in insulators. Phys. Rev. B 94, 125140 (2016).


Google Scholar
 

Shen, H. & Fu, L. Quantum oscillation from in-gap states and a non-Hermitian Landau level problem. Phys. Rev. Lett. 121, 026403 (2018).

PubMed 
CAS 

Google Scholar
 

Lee, P. A. Quantum oscillations in the activated conductivity in excitonic insulators: possible application to monolayer WTe2. Phys. Rev. B 103, L041101 (2021).

CAS 

Google Scholar
 

He, W.-Y. & Lee, P. A. Quantum oscillation of thermally activated conductivity in a monolayer WTe2-like excitonic insulator. Phys. Rev. B 104, L041110 (2021).

CAS 

Google Scholar
 

Allocca, A. A. & Cooper, N. R. Quantum oscillations of magnetization in interaction-driven insulators. SciPost Phys. 12, 123 (2022).


Google Scholar
 

Allocca, A. A. & Cooper, N. R. Fluctuation-dominated quantum oscillations in excitonic insulators. Phys. Rev. Res. 6, 033199 (2024).

CAS 

Google Scholar
 

Zyuzin, V. A. de Haas–van Alphen effect and quantum oscillations as a function of temperature in correlated insulators. Phys. Rev. B 109, 235111 (2024).

CAS 

Google Scholar
 

Zou, B., Zeng, Y., MacDonald, A. H. & Strashko, A. Electrical control of two-dimensional electron-hole fluids in the quantum Hall regime. Phys. Rev. B 109, 085416 (2024).

CAS 

Google Scholar
 

Shao, Y. & Dai, X. Quantum oscillations in an excitonic insulating electron-hole bilayer. Phys. Rev. B 109, 155107 (2024).

CAS 

Google Scholar
 

Sodemann, I., Chowdhury, D. & Senthil, T. Quantum oscillations in insulators with neutral Fermi surfaces. Phys. Rev. B 97, 045152 (2018).

CAS 

Google Scholar
 

Chowdhury, D., Sodemann, I. & Senthil, T. Mixed-valence insulators with neutral Fermi surfaces. Nat. Commun. 9, 1766 (2018).

PubMed 
PubMed Central 

Google Scholar
 

Burg, G. W. et al. Strongly enhanced tunneling at total charge neutrality in double-bilayer graphene-WSe2 heterostructures. Phys. Rev. Lett. 120, 177702 (2018).

PubMed 
CAS 

Google Scholar
 

Wang, Z. et al. Evidence of high-temperature exciton condensation in two-dimensional atomic double layers. Nature 574, 76–80 (2019).

PubMed 
CAS 

Google Scholar
 

Ma, L. et al. Strongly correlated excitonic insulator in atomic double layers. Nature 598, 585–589 (2021).

PubMed 
CAS 

Google Scholar
 

Qi, R. et al. Thermodynamic behavior of correlated electron-hole fluids in van der Waals heterostructures. Nat. Commun. 14, 8264 (2023).

PubMed 
PubMed Central 
CAS 

Google Scholar
 

Nguyen, P. X. et al. Perfect Coulomb drag in a dipolar excitonic insulator. Science 388, 274–278 (2025).

PubMed 
CAS 

Google Scholar
 

Qi, R. et al. Perfect Coulomb drag and exciton transport in an excitonic insulator. Science 388, 278–283 (2025).

PubMed 
CAS 

Google Scholar
 

Qi, R. et al. Electrically controlled interlayer trion fluid in electron-hole bilayers. Preprint at https://arxiv.org/abs/2312.03251 (2023).

Nguyen, P. X. et al. A degenerate trion liquid in atomic double layers. Preprint at https://arxiv.org/abs/2312.12571 (2023).

Du, L. et al. Evidence for a topological excitonic insulator in InAs/GaSb bilayers. Nat. Commun. 8, 1971 (2017).

PubMed 
PubMed Central 

Google Scholar
 

Han, Z., Li, T., Zhang, L. & Du, R.-R. Magneto-induced topological phase transition in inverted InAs/GaSb bilayers. Phys. Rev. Res. 6, 023192 (2024).

CAS 

Google Scholar
 

Fogler, M. M., Butov, L. V. & Novoselov, K. S. High-temperature superfluidity with indirect excitons in van der Waals heterostructures. Nat. Commun. 5, 4555 (2014).

PubMed 
CAS 

Google Scholar
 

Wu, F.-C., Xue, F. & MacDonald, A. H. Theory of two-dimensional spatially indirect equilibrium exciton condensates. Phys. Rev. B 92, 165121 (2015).


Google Scholar
 

Xie, M. & MacDonald, A. H. Electrical reservoirs for bilayer excitons. Phys. Rev. Lett. 121, 067702 (2018).

PubMed 
CAS 

Google Scholar
 

Zeng, Y. & MacDonald, A. H. Electrically controlled two-dimensional electron-hole fluids. Phys. Rev. B 102, 085154 (2020).

CAS 

Google Scholar
 

Eisenstein, J. P. & MacDonald, A. H. Bose–Einstein condensation of excitons in bilayer electron systems. Nature 432, 691–694 (2004).

PubMed 
CAS 

Google Scholar
 

Tiemann, L. et al. Exciton condensate at a total filling factor of one in Corbino two-dimensional electron bilayers. Phys. Rev. B 77, 033306 (2008).


Google Scholar
 

Nandi, D., Finck, A. D. K., Eisenstein, J. P., Pfeiffer, L. N. & West, K. W. Exciton condensation and perfect Coulomb drag. Nature 488, 481–484 (2012).

PubMed 
CAS 

Google Scholar
 

Liu, X., Watanabe, K., Taniguchi, T., Halperin, B. I. & Kim, P. Quantum Hall drag of exciton condensate in graphene. Nat. Phys. 13, 746–750 (2017).

CAS 

Google Scholar
 

Li, J. I. A., Taniguchi, T., Watanabe, K., Hone, J. & Dean, C. R. Excitonic superfluid phase in double bilayer graphene. Nat. Phys. 13, 751–755 (2017).

CAS 

Google Scholar
 

Stier, A. V. et al. Magnetooptics of exciton Rydberg states in a monolayer semiconductor. Phys. Rev. Lett. 120, 057405 (2018).

PubMed 
CAS 

Google Scholar
 

Nagler, P. et al. Giant magnetic splitting inducing near-unity valley polarization in van der Waals heterostructures. Nat. Commun. 8, 1551 (2017).

PubMed 
PubMed Central 

Google Scholar
 

Vu, D. & Das Sarma, S. Excitonic phases in a spatially separated electron-hole ladder model. Phys. Rev. B 108, 235158 (2023).

CAS 

Google Scholar
 

Wang, L. et al. One-dimensional electrical contact to a two-dimensional material. Science 342, 614–617 (2013).

PubMed 
CAS 

Google Scholar
 

Shen, P.-C. et al. Ultralow contact resistance between semimetal and monolayer semiconductors. Nature 593, 211–217 (2021).

PubMed 
CAS 

Google Scholar
 

Ashoori, R. C. et al. Single-electron capacitance spectroscopy of discrete quantum levels. Phys. Rev. Lett. 68, 3088–3091 (1992).

PubMed 
CAS 

Google Scholar