Low loss Ge-on-Si waveguides operating in the 8-14 µm atmospheric transmission window.

Germanium-on-silicon waveguides were modeled, fabricated and characterized at wavelengths ranging from 7.5 to 11 µm. Measured waveguide losses are below 5 dB/cm for both TE and TM polarization and reach values of ∼ 1 dB/cm for ≥ 10 µm wavelengths for the TE polarization. This work demonstrates experimentally for the first time that Ge-on-Si is a viable waveguide platform for sensing in the molecular fingerprint spectral region. Detailed modeling and analysis is presented to identify the various loss contributions, showing that with practical techniques losses below 1 dB/cm could be achieved across the full measurement range.

[1]  Arnan Mitchell,et al.  Mid-infrared octave spanning supercontinuum generation to 8.5 μm in silicon-germanium waveguides , 2018 .

[2]  Corrado Sciancalepore,et al.  Improvement of Sidewall Roughness of Submicron SOI Waveguides by Hydrogen Plasma and Annealing , 2018, IEEE Photonics Technology Letters.

[3]  Anwar Faizd Osman,et al.  Suspended silicon waveguides for long-wave infrared wavelengths. , 2017, Optics letters.

[4]  Wei Du,et al.  Si-Based GeSn Lasers with Wavelength Coverage of 2–3 μm and Operating Temperatures up to 180 K , 2017 .

[5]  Milos Nedeljkovic,et al.  Germanium-on-silicon waveguides operating at mid-infrared wavelengths up to 8.5 μm. , 2017, Optics express.

[6]  M. Myronov,et al.  Mid-infrared light emission > 3 µm wavelength from tensile strained GeSn microdisks. , 2017, Optics express.

[7]  Kazumi Wada,et al.  Mid-IR supercontinuum generated in low-dispersion Ge-on-Si waveguides pumped by sub-ps pulses. , 2017, Optics express.

[8]  P. Biagioni,et al.  n-Ge on Si for mid-infrared plasmonic sensors , 2017, 2017 IEEE Photonics Society Summer Topical Meeting Series (SUM).

[9]  Andrew P. Knights,et al.  Mechanisms for optical loss in SOI waveguides for mid-infrared wavelengths around 2 μm , 2017 .

[10]  P. Biagioni,et al.  Disentangling nonradiative recombination processes in Ge micro-crystals on Si substrates , 2016, 1603.08700.

[11]  Douglas J. Paul,et al.  Mid-Infrared Intersubband Absorption from p-Ge Quantum Wells Grown on Si Substrates , 2016 .

[12]  A. Khokhar,et al.  Germanium-on-silicon Vernier-effect photonic microcavities for the mid-infrared. , 2016, Optics letters.

[13]  Eugenio Calandrini,et al.  Midinfrared Plasmon-Enhanced Spectroscopy with Germanium Antennas on Silicon Substrates. , 2015, Nano letters.

[14]  Milos Nedeljkovic,et al.  Surface-Grating-Coupled Low-Loss Ge-on-Si Rib Waveguides and Multimode Interferometers , 2015, IEEE Photonics Technology Letters.

[15]  Richard Soref,et al.  Predictions of Free-Carrier Electroabsorption and Electrorefraction in Germanium , 2015, IEEE Photonics Journal.

[16]  Werner Schrenk,et al.  Monolithically integrated mid-infrared lab-on-a-chip using plasmonics and quantum cascade structures , 2014, Nature Communications.

[17]  Mark Norman,et al.  Active and passive infrared spectroscopy for the detection of environmental threats , 2014, Sensing Technologies + Applications.

[18]  E. R. Polovtseva,et al.  The HITRAN2012 molecular spectroscopic database , 2013 .

[19]  Douglas J. Paul,et al.  Nanofabrication of high aspect ratio (∼50:1) sub-10 nm silicon nanowires using inductively coupled plasma etching , 2012 .

[20]  N. D. de Rooij,et al.  Cocaine detection by a mid-infrared waveguide integrated with a microfluidic chip. , 2012, Lab on a chip.

[21]  Yu-Chi Chang,et al.  Low-loss germanium strip waveguides on silicon for the mid-infrared. , 2012, Optics letters.

[22]  Richard A. Soref,et al.  The third-order nonlinear optical coefficients of Si, Ge, and Si1−xGex in the midwave and longwave infrared , 2011 .

[23]  R. Soref.  Mid-infrared photonics in silicon and germanium , 2010 .

[24]  S. Spector,et al.  Silicon waveguide sidewall smoothing by wet chemical oxidation , 2005, Journal of Lightwave Technology.

[25]  R. Newman,et al.  Oxygen diffusion and precipitation in Czochralski silicon , 2000 .

[26]  Elia Palange,et al.  Metal–Ge-Si heterostructures for near-infrared light detection , 1999 .

[27]  F. Payne,et al.  A theoretical analysis of scattering loss from planar optical waveguides , 1994 .

[28]  H. Li.  Refractive index of silicon and germanium and its wavelength and temperature derivatives , 1980 .

[29]  R. Newman,et al.  Effect of Impurities on Free-Hole Infrared Absorption in p-Type Germanium , 1957 .

[30]  H. B. Briggs,et al.  New Infrared Absorption Bands in p-Type Germanium , 1952 .