PhD & Postdoc

Ekaterina Romanova

Optoelectronics · Peter the Great St. Petersburg Polytechnic University

Ekaterina Romanova fabricates germanium-on-silicon waveguide circuits that guide mid-infrared light in the 3–12 µm spectral window — where the molecular fingerprint absorption bands of key industrial gases (CO₂, CH₄, NOₓ, and volatile organic compounds) offer parts-per-billion detection sensitivity. At Peter the Great St. Petersburg Polytechnic University's Photonics and Optical Information Technologies department, supervised by Prof. Vladimir Lazarev, she deposits Ge films by plasma-enhanced CVD onto oxidised silicon substrates and patterns single-mode rib waveguide geometries using deep-UV contact lithography. Her FDTD simulations predict and her experiments confirm evanescent-field absorption path lengths of 2–4 cm on a chip 5 mm × 5 mm — a 100-fold path-length advantage over conventional bulk-optic gas cells. Integration of quantum cascade laser coupling and on-chip microfluidic gas cells enables a compact analyser chip that Ekaterina has validated against certified gas mixtures to a CO₂ detection limit of 4 ppm. A Skolkovo innovation grant covers the transition to commercial-grade wafer processing, and a research collaboration with Rosatom's photonics division targets radiation-hard versions for nuclear facility atmosphere monitoring.

Thesis Topic

Integrated Photonic Circuits for Mid-Infrared Chemical Sensing Using Ge-on-Si Waveguide Platforms

Transition Signals