TY - JOUR
T1 - Thickness-dependent polaron crossover in tellurene
AU - Zhang, Kunyan
AU - Fu, Chuliang
AU - Kelly, Shelly
AU - Liang, Liangbo
AU - Kang, Seoung Hun
AU - Jiang, Jing
AU - Zhang, Ruifang
AU - Wang, Yixiu
AU - Wan, Gang
AU - Siriviboon, Phum
AU - Yoon, Mina
AU - Ye, Peide D.
AU - Wu, Wenzhuo
AU - Li, Mingda
AU - Huang, Shengxi
PY - 2025/1/10
Y1 - 2025/1/10
N2 - Polarons, quasiparticles from electron-phonon coupling, are crucial for material properties including high-temperature superconductivity and colossal magnetoresistance. However, scarce studies have investigated polaron formation in low-dimensional materials with phonon polarity and electronic structure transitions. In this work, we studied polarons of tellurene, composed of chiral Te chains. The frequency and linewidth of the A1 phonon, which becomes increasingly polar for thinner tellurene, change abruptly for thickness below 10 nanometers, where field-effect mobility drops rapidly. These phonon and transport signatures, combined with phonon polarity and band structure, suggest a crossover from large polarons in bulk tellurium to small polarons in few-layer tellurene. Effective field theory considering phonon renormalization in the small-polaron regime semiquantitatively reproduces the phonon hardening and broadening effects. This polaron crossover stems from the quasi-one-dimensional nature of tellurene, where modulation of interchain distance reduces dielectric screening and promotes electron-phonon coupling. Our work provides valuable insights into the influence of polarons on phononic, electronic, and structural properties in low-dimensional materials.
AB - Polarons, quasiparticles from electron-phonon coupling, are crucial for material properties including high-temperature superconductivity and colossal magnetoresistance. However, scarce studies have investigated polaron formation in low-dimensional materials with phonon polarity and electronic structure transitions. In this work, we studied polarons of tellurene, composed of chiral Te chains. The frequency and linewidth of the A1 phonon, which becomes increasingly polar for thinner tellurene, change abruptly for thickness below 10 nanometers, where field-effect mobility drops rapidly. These phonon and transport signatures, combined with phonon polarity and band structure, suggest a crossover from large polarons in bulk tellurium to small polarons in few-layer tellurene. Effective field theory considering phonon renormalization in the small-polaron regime semiquantitatively reproduces the phonon hardening and broadening effects. This polaron crossover stems from the quasi-one-dimensional nature of tellurene, where modulation of interchain distance reduces dielectric screening and promotes electron-phonon coupling. Our work provides valuable insights into the influence of polarons on phononic, electronic, and structural properties in low-dimensional materials.
UR - http://www.scopus.com/inward/record.url?scp=85215112602&partnerID=8YFLogxK
U2 - 10.1126/sciadv.ads4763
DO - 10.1126/sciadv.ads4763
M3 - Article
C2 - 39772675
AN - SCOPUS:85215112602
SN - 2375-2548
VL - 11
SP - eads4763
JO - Science Advances
JF - Science Advances
IS - 2
ER -