Crafting Tomorrow's Internet with Etchless Photonics
In the heart of a Hong Kong lab, a revolution brews—one measured in nanometers and photons.
Dr. Zhe-Long Jin, whose recent Ph.D. defense on August 4, 2025, marked a milestone in photonics, stands at the forefront of a technological leap. His work on etchless integrated photonics tackles a critical bottleneck: traditional chip fabrication methods damage delicate optical materials, limiting efficiency. By harnessing exotic light states called Bound States in the Continuum (BICs), Jin's innovations could transform quantum computing, AR displays, and ultra-fast communications. For Jin, light isn't just a tool—it's a material to sculpt, a highway to build, and a key to unlocking an interconnected future 5 .
Traditional photonic chips rely on etching patterns into materials like silicon or lithium niobate (LN). This process creates surface defects that scatter light, capping efficiency. Jin's approach eliminates etching entirely. Instead, his team uses:
This preserves material integrity, enabling record-breaking Q factors (a measure of light storage efficiency) exceeding 10 million—critical for quantum memory and precision sensors 5 .
In a landmark 2025 study, Jin's team engineered Floquet-Bloch oscillations—light waves that "dance" in time-controlled periodic structures. Unlike static chips, these dynamic systems:
This breakthrough, published in Laser & Photonics Reviews, paves the way for self-correcting optical networks 5 .
Objective: Create ultra-low-loss lithium tantalate (LT) microring resonators for quantum applications.
The team achieved resonators with:
| Resonator Type | Q Factor | Loss (dB/cm) | Application |
|---|---|---|---|
| Traditional Etched | 1–2 million | 3.0 | Data transmission |
| Jin's Etchless LT | >10 million | 0.05 | Quantum memory/sensors |
This 10× efficiency leap means photons circulate 10× longer, enabling complex light-matter interactions for quantum processors 5 .
Jin's work relies on meticulously chosen materials:
Function: Core resonator material
Innovation: Higher nonlinearity than LN for light control
Function: Selective SiO₂ removal
Innovation: Creates smooth interfaces without etching damage
Function: Edge polishing
Innovation: Achieves atomic-scale surface smoothness
Function: Sputtering for electrodes
Innovation: Minimizes light absorption in waveguides
Function: Cleaning without residue
Innovation: Preserves optical clarity
Jin's etchless photonics isn't just academic—it's accelerating real-world tech:
High-Q resonators could store quantum data for milliseconds (a lifetime for qubits).
Efficient lasers enable brighter, smaller displays.
Floquet-Bloch modulators handle terahertz data streams.
"We're not just building chips—we're weaving light into the fabric of connectivity."
Zhe-Long Jin's journey—from defending his thesis to pioneering etchless photonics—exemplifies science's quiet revolutions. His BIC-based platforms, once confined to journals, now underpin prototypes in labs from Zurich to Tokyo. In a world hungry for faster, greener tech, Jin's light-weaving offers more than speed; it offers a path to lossless communication. As photons replace electrons, the etchless revolution may well light the way to tomorrow's internet 5 .
"The perfect resonator isn't etched—it's grown, polished, and coaxed into being. Like light itself, it demands patience, precision, and a touch of wonder."