Charged bosons made of fermions in a solid state system without Cooper pairing

Z. Sun; J. Beaumariage; Q. Wan; H. Alnatah; N. Hougland; J. Chisholm; Q. Cao; K. Watanabe; T. Taniguchi; B. Hunt; I. V. Bondarev; D. W. Snoke

arXiv · 2003.05850

Charged bosons made of fermions in a solid state system without Cooper pairing

Z. Sun·J. Beaumariage·Q. Wan·H. Alnatah·N. Hougland·J. Chisholm·Q. Cao·K. Watanabe·T. Taniguchi·B. Hunt·I. V. Bondarev·D. W. Snoke

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Abstract

We report experimental evidence for charged boson states in a solid without Cooper pairing, based on attaching two free carriers to an exciton in a semiconducting system. Theoretical calculations show that this type of complex is stable in bilayer systems next to a parallel metal layer. Our experimental measurements on structures made using two different materials show a new spectral line at the predicted energy, if and only if all the required conditions for this complex are fulfilled, including a parallel metal layer that significantly screens the repulsive interaction between the like-charge carriers, and with the predicted dependence on the distance to the metal layer. This suggests a new path for pursuing room temperature superconductivity without Cooper pairing.

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Z. Sun, J. Beaumariage, Q. Wan, H. Alnatah, N. Hougland, J. Chisholm, Q. Cao, K. Watanabe, T. Taniguchi, B. Hunt, I. V. Bondarev, D. W. Snoke. 2020-03-12. Charged bosons made of fermions in a solid state system without Cooper pairing. https://arxiv.org/abs/2003.05850

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