Scholarlink

<p>Revealing the hidden interactions that bind electronic and lattice components of cooperative quantum order is central to sculpting new states of matter. This challenge is epitomized by the charge density wave material 1<i>T</i>-TiSe<sub>2</sub>, where photoexcitation disrupts its presumed hybrid exciton-phonon order: the electronic component collapses within femtoseconds, while the periodic lattice distortion persists, challenging the definition of hybrid order. Here we resolve this paradox by uncovering a low-frequency mode (~0.13&#xa0;THz) that emerges only in the ordered state and signals exciton-phonon coupling. This mode is consistent with a locked phason, a collective excitation arising when excitonic and lattice degrees of freedom share a coupled potential landscape. At a critical photoexcitation threshold, the collapse of the excitonic order flattens this potential, causing the locked phason to disappear, the charge density wave phonon to selectively overheat, and the surviving lattice distortion to become a trapped non-thermal remnant.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Tracking the catastrophic collapse of hybrid exciton-phonon order in a quantum material

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年7月30日

查看全文
  • Omar Abdul-Aziz,
  • Danilo Comini,
  • Johannes Lang,
  • Nils Bartel,
  • Michael Buchhold,
  • Sebastian Diehl,
  • Daniel Wolverson,
  • Charles J. Sayers,
  • Giulio Cerullo,
  • Paul H. M. van Loosdrecht,
  • Hamoon Hedayat

摘要

Revealing the hidden interactions that bind electronic and lattice components of cooperative quantum order is central to sculpting new states of matter. This challenge is epitomized by the charge density wave material 1T-TiSe2, where photoexcitation disrupts its presumed hybrid exciton-phonon order: the electronic component collapses within femtoseconds, while the periodic lattice distortion persists, challenging the definition of hybrid order. Here we resolve this paradox by uncovering a low-frequency mode (~0.13 THz) that emerges only in the ordered state and signals exciton-phonon coupling. This mode is consistent with a locked phason, a collective excitation arising when excitonic and lattice degrees of freedom share a coupled potential landscape. At a critical photoexcitation threshold, the collapse of the excitonic order flattens this potential, causing the locked phason to disappear, the charge density wave phonon to selectively overheat, and the surviving lattice distortion to become a trapped non-thermal remnant.