| Title |
Voltage Bias Effect on Light-Induced Bistable Switching in Two-Terminal Device Based on VO2 Thin Films |
| DOI |
http://doi.org/10.5207/JIEIE.2025.39.6.448 |
| Keywords |
Hysteresis width; Joule heat; Memory application; Optical bistability; Vanadium dioxide |
| Abstract |
In this manuscript, we experimentally investigate the effect of DC voltage bias on laser-induced bistable switching behavior in a two-terminal device based on vanadium dioxide (VO2) thin films. To explore this phenomenon, a DC voltage source was connected in series with the device and a resistor to form a closed-loop circuit. The static and transient responses of the circuit current (I) were measured as the optical power (PL) of a ~1.55μm laser beam, incident on the VO2 film, was varied under different bias voltages (VS). In the static response, current I exhibited hysteresis with respect to PL, but only within a narrow range of VS (6 ~ 9 V). Within this range, decreasing VS shifted the hysteresis loop toward higher PL values and narrowed its width, while increasing VS had the opposite effect. Outside this voltage range (VS < 6 V or VS > 9 V), the hysteresis behavior disappeared. At low VS, the device showed no switching, and at high VS, the switching became irreversible rather than bistable. In the transient response, clear laser-induced bistable switching was observed only in a narrower VS range (8 ~ 9 V), suggesting that dynamic bistability requires more stringent bias conditions compared to static hysteresis. |