000206751 001__ 206751
000206751 005__ 20181203023817.0
000206751 0247_ $$2doi$$a10.1103/PhysRevLett.114.047402
000206751 022__ $$a1079-7114
000206751 02470 $$2ISI$$a000349871400010
000206751 037__ $$aARTICLE
000206751 245__ $$aMeasurements of the Electric Field of Zero-Point Optical Phonons in GaAs Quantum Wells Support the Urbach Rule for Zero-Temperature Lifetime Broadening
000206751 260__ $$bAmer Physical Soc$$c2015$$aCollege Pk
000206751 269__ $$a2015
000206751 300__ $$a6
000206751 336__ $$aJournal Articles
000206751 520__ $$aWe study a specific type of lifetime broadening resulting in the well-known exponential "Urbach tail" density of states within the energy gap of an insulator. After establishing the frequency and temperature dependence of the Urbach edge in GaAs quantum wells, we show that the broadening due to the zero-point optical phonons is the fundamental limit to the Urbach slope in high-quality samples. In rough analogy with Welton's heuristic interpretation of the Lamb shift, the zero-temperature contribution to the Urbach slope can be thought of as arising from the electric field of the zero-point longitudinal-optical phonons. The value of this electric field is experimentally measured to be 3 kV cm(-1), in excellent agreement with the theoretical estimate.
000206751 700__ $$aBhattacharya, Rupak
000206751 700__ $$aMondal, Richarj
000206751 700__ $$aKhatua, Pradip
000206751 700__ $$0240082$$g106305$$aRudra, Alok
000206751 700__ $$0240239$$g105530$$aKapon, Eli
000206751 700__ $$aMalzer, Stefan
000206751 700__ $$aDöhler, Gottfried
000206751 700__ $$aPal, Bipul
000206751 700__ $$aBansal, Bhavtosh
000206751 773__ $$j114$$tPhysical Review Letters$$k4
000206751 909C0 $$xU10158$$0252035$$pLPN
000206751 909CO $$pSB$$particle$$ooai:infoscience.tind.io:206751
000206751 917Z8 $$x182258
000206751 937__ $$aEPFL-ARTICLE-206751
000206751 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000206751 980__ $$aARTICLE