sSNOM Upgrade for University of Manchester

Concepts

• teddington
• precision equipment
• university
• ssnom
• manchester
• laboratory and optical equipment
• pump probe
• attocube systems ag
• temporal overlap
• customized fiber patch cord

Location

Photon Science Institute, University of Manchester, M13 9PL

Description

Upgrade enabling time-resolved pump-probe spectroscopy for cryogenic THz-TDS near-field measurements. The pump laser must be synchronized with the existing THz-TDS spectroscopy and cryogenic near-field systems. The upgrade includes a laser amplifier unit with free-space coupled optical output at 780nm, 100MHz rep rate, pulse energy >1.3nJ, >140mW output power, and customized fiber patch cord for temporal overlap of pump-probe pulses. Additionally, a transmission module enables static pump-probe measurements in transmission, where the sample is pumped via a diffraction-limited beam from the bottom and probed by amplitude- & phase-resolved near-field measurements (pseudo-heterodyne detection) from the top.

Total Quantity or Scope

Upgrade for cryo-neaSCOPE+xs s-SNOM system can only be provided by the base system’s manufacturer – attocube systems AG. Needs and requirements include: 1. Ultra-fast spectroscopy software module for THz-TDS • Enables pump-probe spectroscopy for THz-TDS in neaSCAN • Provides software control of all delays and components for ready-to-use results • Allows acquisition of time-resolved spectra with down to 40 fs temporal resolution 2. Synchronized Transmission-Mode Detection Module • Enables bottom-side sample illumination in transmission-mode with broadband parabolic mirror (NA=0.44) • Enables simultaneous detection of optical near-field amplitude & phase • Motorized parabolic mirror for beam-alignment • Stationary focal point with respect to AFM-tip • Variable illumination spot size (ca. 2μm - 100μm) • Suitable for plane-wave illumination • Exchangeable beam-splitter mount • Supports stationary focal point with respect to sample position (bottom-side illumination synchronized with sample scanner) • Support AFM scan-speed: up to 20 μm/s @ highest spatial resolution 3. Software Development Kit for neaSCAN 4. THz Pump-Probe operation • additional delay line & synchronized software control for pump probe • amplifier unit with free-space coupled optical output at 780nm with amplifier unit mounted on optical table next to neaSNOM microscope • 100MHz rep rate, pulse energy >1.3nJ, >140mW output power • Customized fiber patch cord for temporal overlap of pump-probe pulses

Award Detail

CPV Codes

• 38000000 - Laboratory, optical and precision equipments (excl. glasses)

Indicators

Legal Justification

Attocube systems AG is the only company worldwide, who manufactures a scattering-type near-field optical microscope (our pre-upgrade system) that enables simultaneous background-free imaging and spectroscopy on nanometre length scales in the visible-IR-THz range. Their exclusive design works with the following patents: • Patented parabolic mirror design for focusing and collection of light • Patented dual-port design to allow two beams of light to be focused on the atomic force microscope (AFM) tip for nanoscale imaging and spectroscopy • Patented signal processing for optical background suppression • Patented pseudo-heterodyne detection (PsHet) technology for background suppression • Patented interferometric design (nano-FTIR) for background-free optical detection technology and simultaneous detection of optical amplitude and phase and hyperspectral imaging • Patented high speed holography for multispectral imaging • Patented phase shifting detection to extract relative phase These patents and the exclusive design have enabled the neaSCOPE system to conduct amplitude and phase-resolved vector field, reflection, and absorption mapping with nanoscale spatial resolution. It is currently the only solution provider on the market that enables dual-port s-SNOM operation combined with a high NA parabolic mirror, which is essential for low SNR THz TDS and pump-probe measurements. In particular, attocube systems AG is the only company who can upgrade the existing cryogenic s-SNOM system (cryo-neaSCOPE) based at University of Manchester to perform nanoscale THz-TDS and pump-probe imaging and spectroscopy at low temperature. Therefore, the same manufacture of the pre-upgraded s-SNOM system is required to ensure: • All upgrade subsystems must be compatible with the existing microscope controls (both in hardware and software), while still being amplitude- & phase-resolved and background-free. • Pump laser must be electronically synchronized with the existing cryogenic THz-TDS spectroscopy system • Excitation wavelength must be compatible with optical windows in the cold shroud of the existing cryo-neaSCOPE system