USTC Sets Record for 393nm-to-1550nm Quantum Frequency Conversion

Researchers at USTC demonstrated low-noise quantum frequency conversion from 393 nm to the 1550 nm telecom band, a step toward linking trapped-ion quantum memories over long optical fibers. The module reached 28.8% end-to-end efficiency with pump noise suppressed to 35 counts per second — about 30 times more efficient and over two orders of magnitude quieter than previous work.

• Conversion efficiency from 393 nm to 1550 nm reached 28.8%
• Pump noise suppressed to 35 counts per second
• About 30 times more efficient than previous work
• Module achieved a 120:1 signal-to-noise ratio with calcium-40 ion qubits