Lasing and Anti-Lasing in a Single Cavity
(A) SEM image of the device. (B) Coherent amplification and absorption of ±15 dB are attained at the same wavelength of 1555.8 nm.
We experimentally demonstrated lasing and anti-lasing at the same frequency in a single device
Significance and Impact
Offers a new route for light modulation with extremely high contrast approaching the ultimate limit
- Laser and anti-laser (or coherent perfect absorber) fundamentally contradict each other
- By carefully engineering the loss (Cr/Ge) and gain (InGaAsP) materials to satisfy the parity-time symmetric condition, lasing and anti-lasing can both be attained in a single device
- In-phase coherent amplification (due to lasing mode) and coherent absorption (due to anti-lasing mode) are experimentally observed at the same wavelength using a pump-probe measurement setup