Abstract
We report on the optical-gain properties of channel waveguides patterned into lattice-matched KGdxLuyEr1-x-y(WO4)2 layers grown onto undoped KY(WO4)2 substrates by liquid phase epitaxy. A systematic investigation of gain is performed for five different Er3+ concentrations in the range of 0.75 to 10at.% and different pump powers and signal wavelengths. In pump-probe-beam experiments, relative internal gain, i.e., signal enhancement minus absorption loss of light propagating in the channel waveguide, is experimentally demonstrated, with a maximum value of 12 ± 5 dB/cm for signals at the peak-emission wavelength of 1534.7 nm.
Highlights
The great success of erbium-doped fiber amplifiers near 1.5 μm has triggered significant research on host materials and fabrication techniques for erbium-doped waveguide amplifiers (EDWA) [1,2,3,4,5]
The aim to compensate these losses has fueled the demand for on-chipintegrated host materials with erbium concentrations exceeding 1020 cm−3 to increase the gain in EDWAs
A record-high optical gain of ~1000 dB/cm at 981 nm was demonstrated in an ytterbiumdoped potassium double tungstate channel-waveguide amplifier [15]
Summary
The great success of erbium-doped fiber amplifiers near 1.5 μm has triggered significant research on host materials and fabrication techniques for erbium-doped waveguide amplifiers (EDWA) [1,2,3,4,5]. Erbium doped into crystalline materials has been the subject of recent investigations to increase the maximum achievable gain in waveguide amplifiers [12,13]. A record-high optical gain of ~1000 dB/cm at 981 nm was demonstrated in an ytterbiumdoped potassium double tungstate channel-waveguide amplifier [15]. In this family of host materials [16], rare-earth ions exhibit among the highest transition cross-sections reported so far [17,18,19,20], making these materials very promising for integrated amplifiers. We report on the fabrication and experimental characterization of optical gain in erbium-doped potassium gadolinium lutetium double tungstate, KGdxLuyEr1-xy(WO4), waveguide amplifiers. A relative internal gain of 12 ± 5 dB/cm at 1534.7 nm is demonstrated for an erbium concentration of 6at.% with a potentially exploitable bandwidth of ~116 nm
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
