Large negative thermo-optic coefficients of a lead halide perovskite

• DOI: 10.1126/sciadv.aax0786
• Publication Date: 2019-07-19T23:15:24Z
• Authors: Taketo Handa; Hirokazu Tahara; Tomoko Aharen; Yoshihiko Kanemitsu
• Keywords: Lead (geology)

Lead halide perovskites are promising semiconductors for high-performance photonic devices. Because the refractive index determines optimal design and performance limit of semiconductor devices, its change upon external modulations most critical properties advanced applications. Here, we report that perovskite CH3NH3PbCl3 shows a distinct decrease with increasing temperature, i.e., large negative thermo-optic coefficient, which is opposite to those conventional inorganic semiconductors. By using this demonstrate compensation thermally induced optical phase shifts occurring in Furthermore, observe slow during photoirradiation clarify origin be very low thermal conductivity supported by theoretical analysis. The giant response facilitates efficient modulation visible light.