2008/02/22 by B. Bucher, Benno Bucher, Tuson Park +7 · 1 citation
Engineering · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #FOS: Physical sciences #Perovskite Materials and Applications #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.0802.3354
4 pages, 4 figures
openalex publication_date 2008/02/22 · arxiv created 2008/02/24 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In the 1960s speculations arose if a ground state exists in solid state materials with an electron and a hole bound to a pair with their spins added to integer values, i.e. excitons. Here we show that electrons and holes in TmSe0.45Te0.55 do form excitons as the thermodynamical ground state. The formation of a large number of excitons in an indirect gap semiconductor requires momentum conservation by means of phonons and, hence, implies a significant change of the heat capacity of the lattice, as found experimentally. The thermodynamically derived phase diagram sustains a bosonic ground state in condensed matter.