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Reconfigurable or programmable photonic devices are rapidly growing and have become an integral part of many optical systems. The ability to selectively modulate electromagnetic waves through electrical stimuli is crucial in the advancement of a variety of applications from data communication and computing devices to environmental science and space explorations. Chalcogenide‐based phase‐change materials (PCMs) are one of the most promising material candidates for reconfigurable photonics due to their large optical contrast between their different solid‐state structural phases. Although significant efforts have been devoted to accurate simulation of PCM‐based devices, in this paper, three important aspects which have often evaded prior models yet having significant impacts on the thermal and phase transition behavior of these devices are highlighted: the enthalpy of fusion, the heat capacity change upon glass transition, as well as the thermal conductivity of liquid‐phase PCMs. The important topic of switching energy scaling in PCM devices, which also helps explain why the three above‐mentioned effects have long been overlooked in electronic PCM memories but only become important in photonics, is further investigated. These findings offer insight to facilitate accurate modeling of PCM‐based photonic devices and can inform the development of more efficient reconfigurable optics.
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Robust Electrothermal Switching of Optical Phase‐Change Materials through Computer‐Aided Adaptive Pulse Optimization
Electrically tunable optical devices present diverse functionalities for manipulating electromagnetic waves by leveraging elements capable of reversibly switching between different optical states. This adaptability in adjusting their responses to electromagnetic waves after fabrication is crucial for developing more efficient and compact optical systems for a broad range of applications, including sensing, imaging, telecommunications, and data storage. Chalcogenide‐based phase‐change materials (PCMs) have shown great promise due to their stable, nonvolatile phase transition between amorphous and crystalline states. Nonetheless, optimizing the switching parameters of PCM devices and maintaining their stable operation over thousands of cycles with minimal variation can be challenging. Herein, the critical role of PCM pattern as well as electrical pulse form in achieving reliable and stable switching is reported on, extending the operational lifetime of the device beyond 13000 switching events. To achieve this, a computer‐aided algorithm that monitors optical changes in the device and adjusts the applied voltage in accordance with the phase transformation process is developed, thereby significantly enhancing the lifetime of these reconfigurable devices. The findings reveal that patterned PCM structures show significantly higher endurance compared to blanket PCM thin films.
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- Award ID(s):
- 2225968
- PAR ID:
- 10523320
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- physica status solidi (RRL) – Rapid Research Letters
- ISSN:
- 1862-6254
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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