Parity-forbidden excitations of Sr2CuO2Cl2 revealed by optical third-harmonic spectroscopy - art. no. 127006

Authors
Schumacher, AB Dodge, JS Carnahan, MA Kaindl, RA Chemla, DS Miller, LL
Citation
Ab. Schumacher et al., Parity-forbidden excitations of Sr2CuO2Cl2 revealed by optical third-harmonic spectroscopy - art. no. 127006, PHYS REV L, 8712(12), 2001, pp. 7006
Citations number
21
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
8712
Issue
12
Year of publication
2001
Database
ISI
SICI code
0031-9007(20010917)8712:12<7006:PEOSRB>2.0.ZU;2-Y
Abstract
We present the first study of nonlinear optical third-harmonic generation ( THG) in the strongly correlated charge-transfer insulator Sr2CuO2Cl2. For f undamental excitation in the. near infrared, the THG spectrum reveals a str ongly resonant response for photon energies near 0.7 eV. Polarization analy sis reveals this novel resonance to, be only partially accounted for by thr ee-photon excitation to the optical charge-transfer exciton, and indicates that an even-parity state at 2 eV. with a(1g) symmetry, participates in the third-harmonic susceptibility.