Observation of laser cooling on an electric-dipole-allowed transition in Cr3+:LiSAF crystal.
SILVA, Junior Reis; ANDRADE, Luis Humberto da Cunha; LIMA, Sandro Marcio; BENTO, Antonio Carlos; CATUNDA, Tomaz; RAND, Stephen Colby.
SILVA, Junior Reis; ANDRADE, Luis Humberto da Cunha; LIMA, Sandro Marcio; BENTO, Antonio Carlos; CATUNDA, Tomaz; RAND, Stephen Colby.
Abstract: In this work, an electric dipole allowed transition in two Cr3+:LiSAF samples is investigated for the purpose of optical refrigeration. A cooling efficiency approaching 10% is experimentally determined using a mode-mismatched dual-beam thermal lens method with excitation wavelength, , of 1 µm in an unoriented 1% Cr3+:LiSAF, which has an average emission wavelength, , of 850 nm. In an oriented 4% Cr3+:LiSAF sample, the efficiency reached (but does not exceed) the threshold for cooling when excited with p-polarized light. These results suggest that Cr3+:LiSAF can approach an ideal cooling efficiency ~ with excitation ?1µm. Additionally, this analysis indicates that parasitic background absorption rather than upconversion or excited state absorption limits the cooling at higher Cr3+ concentrations.
@article={003252696,author = {SILVA, Junior Reis; ANDRADE, Luis Humberto da Cunha; LIMA, Sandro Marcio; BENTO, Antonio Carlos; CATUNDA, Tomaz; RAND, Stephen Colby.},title={Observation of laser cooling on an electric-dipole-allowed transition in Cr3+:LiSAF crystal},journal={Advanced Optical Materials},note={v. 15, n. 16, p. 2403222-1-2403222-7},year={2025}}