Publications by authors named "M Pruessner"

Polarization management, and in particular polarization rotation, is becoming increasingly important for photonic integrated circuits (PICs). While fiber-optic networks are generally polarization insensitive, the large aspect ratio of high-index-contrast PIC waveguides leads to a large polarization-dependent response of integrated components such as waveguides, optical cavities, couplers, etc. Although foundry-processed polarization rotators operating at telecom and datacom wavelengths (C- and O-band) have been demonstrated, to date, there have been few reports of devices operating at shorter wavelengths.

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  • Silicon photonic integrated circuit foundries allow for the creation of compact electro-optic systems-on-a-chip used in various applications like data communication, lidar, and chemical sensing.
  • A novel broadband silicon waveguide light source has been developed, using a reverse-biased p-i-n diode to emit near-infrared light, producing useful optical power with minimal electrical current.
  • This advancement can enhance the functionality of photonic components and enable applications in metrology, spectroscopy, and sensing without altering current manufacturing processes.
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  • Waveguide-enhanced Raman spectroscopy (WERS) is a technique used for sensing chemicals and biological elements, which operates effectively at visible wavelengths to improve Raman scattering intensity.
  • WERS has traditionally struggled with high losses and low yields due to custom materials, but this study presents a silicon nitride (SIN) platform created using standard CMOS technology.
  • Results show that while a 785 nm configuration offers the best signal-to-background ratio, using a 633 nm pump wavelength helps maximize Stokes signal over a wider spectral range.
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Optical fibers are generally polarization-insensitive while photonic integrated circuits (PICs) often exhibit a large polarization dependence due to the high-aspect-ratio and high-index-contrast of integrated waveguides. As PICs become more mature there is an increasing need for tunable polarization management on-chip. Although micro-electro-mechanical systems (MEMS) are increasingly finding application in PICs for optical switching and phase shifting, they have so far not found wide application for polarization management.

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The stress-vulnerability model has been repeatedly highlighted in relation to the risk, onset and course of psychosis, and has been independently studied in clinical high-risk (CHR) and first-episode psychosis (FEP) populations. Notable in this literature, however, is that there are few studies directly comparing markers of stress response across progressive stages of illness. Here we examined the psychobiological response to the Trier Social Stress Test in 28 CHR (mean age 19.

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