Impurity-doped micro-lasers

2013 EMN Fall Meeting Program&Abstracts

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A35: Impurity-doped Micro-lasers Markus Pollnau

MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands Email: m.pollnau@utwente.nl

Recently rare-earth-ion-doped dielectric channel waveguides have proven their ability to generate highly efficient laser output in the fundamental mode. Here we review our recent achievements obtained in crystalline potassium double tungstates and amorphous aluminum oxide.

Rare-earth-ion-doped monoclinic potassium double tungstates KY(WO4)2, KGd(WO4)2, and KLu(WO4)2 are excellent host materials for solid-state lasers [1]. High-quality KY(WO4)2 optical waveguides were grown and laser operation was demonstrated for the first time [2]. Co-doping a KY(WO4)2 layer with Gd3+ and Lu3+ ions allows for lattice-matched layers with increased refractive index contrast with respect to the KY(WO4)2 substrate [3]. Waveguide laser operation was observed at 1025 nm. 195 mW output power and 82.3% slope efficiency were obtained [4]. In KGd1-xLux(WO4)2:Yb3+ channel waveguides microstructured by Ar+ beam etching [5], we produced 418 mW of continuous-wave output power at 1023 nm with 71% slope efficiency at 981 nm and achieved a record-low quantum defect of 0.7% [6]. Laser experiments on planar [7] and ridge-type channel waveguides [8] in KY1-x-yGdxLuy(WO4)2:Tm3+ demonstrated a slope efficiency of >80% and output powers up to 1.6 W around 2 μm [9,10].

Rare-earth-ion-doped Al2O3 planar waveguides were deposited onto thermally oxidized silicon wafers [11]. Ridge-type channel waveguides with propagation losses as low as 0.2 dB/cm were microstructured into these layers [12]. For Er3+ concentrations of 121020 cm-3, a peak gain of 2.0 dB/cm was measured at 1533 nm [13]. Efficient, ultra-narrow-linewidth distributed-feedback channel waveguide lasers [14] were demonstrated in Al2O3:Er3+ at 1542 nm [15] and Al2O3:Yb3+ at 1022 nm [16], the former with a linewidth of 1.7 kHz, corresponding to a laser Q-factor [17] of 1.141011, and the latter with a slope efficiency of 67% versus launched pump power and output powers up to 55 mW. In a dual-wavelength channel waveguide laser in Al2O3:Yb3+, a 9-kHz-linewidth microwave signal at ~15 GHz was created via the heterodyne photo-detection of the two laser wavelengths [18]. With this laser, we performed intra-laser-cavity optical sensing, resulting in the detection of microspheres with diameters down to 500 nm [19].

[1] M. Pollnau, Y.E. Romanyuk, F. Gardillou, C.N. Borca, U. Griebner, S. Rivier, and V. Petrov, IEEE J. Sel. Top. Quantum Electron. 13, 661 (2007).

[2] Y.E. Romanyuk, C.N. Borca, M. Pollnau, S. Rivier, V. Petrov, and U. Griebner, Opt. Lett. 31, 53 (2006).

[3] F. Gardillou, Y.E. Romanyuk, C.N. Borca, R.P. Salathé, and M. Pollnau, Opt. Lett. 32, 488 (2007). [4] D. Geskus, S. Aravazhi, E. Bernhardi, C. Grivas, S. Harkema, K. Hametner, D. Günther, K. Wörhoff,

and M. Pollnau, Laser Phys. Lett. 6, 800 (2009).

[5] D. Geskus, S. Aravazhi, C. Grivas, K. Wörhoff, and M. Pollnau, Opt. Express 18, 8853 (2010). [6] D. Geskus, S. Aravazhi, K. Wörhoff, and M. Pollnau, Opt. Express 18, 26107 (2010).

[7] S. Rivier, X. Mateos, V. Petrov, U. Griebner, Y.E. Romanyuk, C.N. Borca, F. Gardillou, and M. Pollnau, Opt. Express 15, 5885 (2007).

[8] K. van Dalfsen, S. Aravazhi, D. Geskus, K. Wörhoff, and M. Pollnau, Opt. Express 19, 5277 (2011). [9] K. van Dalfsen, S. Aravazhi, C. Grivas, S.M. García-Blanco, and M. Pollnau, Opt. Lett. 37, 887

(2012).

[10] K. van Dalfsen, S. Aravazhi, C. Grivas, S.M. García-Blanco, and M. Pollnau, Conference on Lasers and Electro-Optics Europe, Munich, Germany, 2013, postdeadline paper PD-A.4.

[11] K. Wörhoff, J.D.B. Bradley, F. Ay, D. Geskus, T.P. Blauwendraat, and M. Pollnau, IEEE J. Quantum Electron. 45, 454 (2009).

[12] J.D.B. Bradley, F. Ay, K. Wörhoff, and M. Pollnau, Appl. Phys. B 89, 311 (2007).

[13] J.D.B. Bradley, L. Agazzi, D. Geskus, F. Ay, K. Wörhoff, and M. Pollnau, J. Opt. Soc. Am. B 27, 187 (2010).

[14] E.H. Bernhardi, Q. Lu, H.A.G.M. van Wolferen, K. Wörhoff, R.M. de Ridder, and M. Pollnau, Photon. Nanostruct. 9, 225 (2011).

[15] E.H. Bernhardi, H.A.G.M. van Wolferen, L. Agazzi, M.R.H. Khan, C.G.H. Roeloffzen, K. Wörhoff, M. Pollnau, and R.M. de Ridder, Opt. Lett. 35, 2394 (2010).

2013 EMN Fall Meeting Program&Abstracts

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[16] E.H. Bernhardi, H.A.G.M. van Wolferen, K. Wörhoff, R.M. de Ridder, and M. Pollnau, Opt. Lett. 36, 603 (2011).

[17] M. Eichhorn and M. Pollnau, "The theory of continuous-wave lasers in the spot light of the vacuum photon", submitted (2013).

[18] E.H. Bernhardi, M.R.H. Khan, C.G.H. Roeloffzen, H.A.G.M. van Wolferen, K. Wörhoff, R.M. de Ridder, and M. Pollnau, Opt. Lett. 37, 181 (2012).

[19] E.H. Bernhardi, K.O. van der Werf, A.J.F. Hollink, K. Wörhoff, R.M. de Ridder, V. Subramaniam, and M. Pollnau, Laser Photonics Rev. 7, 589 (2013).