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Abstract The high transmission speed of optical signals and their application in optical computation have created a growing demand for photon‐programmed memory devices. Rather than using electrical pulses to store data in one of two states, the photomemory (PM) devices exploit the optical stimulation to store the light information. In this work, the application of a nonvolatile rewritable PM array using the photochromic inorganic perovskite CsPbIBr2grown by a vapor‐deposition process is demonstrated. Reversible phase transitions between orthorhombic (δ) and cubic (α) phases are achieved in CsPbIBr2films through laser‐induced heat and moisture exposure. The PM pixels in an optically absorbing perovskite phase exhibit ≈50‐fold photoresponsivity as large as those in a transparent‐colored non‐perovskite phase. Storing optical data are achieved by heating pixels through a near‐infrared laser, while moisture exposure is used to erase the stored information. The nonvolatile PM array exhibits great write‐read‐erase cycle endurance and data retention capability without obvious performance degradation after storage in air for one week. This work demonstrates the promising application of vapor‐deposited inorganic perovskite for optical information storage and the unique potential of them for use in optical switches, tunable metasurfaces, and many other applications.
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High temperature, experimental thermal memory based on optical resonances in photonic crystal slabs
We present an experimental thermal memory with direct optical control and readout. Information is stored in the internal temperature of the device, while laser illumination is used to read, write, and erase stored bits. Our design is based on an absorptive optical resonance in a silicon photonic crystal slab. When the slab is illuminated by a laser with a wavelength close to the resonance, the optical absorption is nonlinear with power, resulting in thermo-optic bistability. We experimentally demonstrate bistability in a fabricated device and show the reading, writing, and erasing of a single memory bit. A hybrid optothermal model shows good agreement with the experiment. Time dependent measurements show that the experimental write/erase times are less than 500 µs. We demonstrate that memory reliability is maintained over 106 cycles, with less than 3% change in the transmission values for the memory ON and OFF states. Our approach allows operation in high temperature and/or highly fluctuating temperature environment up to 100 °C or greater.
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- Award ID(s):
- 1711268
- PAR ID:
- 10594211
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- APL Photonics
- Volume:
- 4
- Issue:
- 1
- ISSN:
- 2378-0967
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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