Facilities/Experimental techniques

In-house facilities

Our laboratory, besides using state-of-the-art commercial equipment, puts a great emphasis on the development of new experimental techniques. The in-house equipment are listed below. We profit from the Center of MicroNanoTechnology (CMI) and Interdisciplinary Centre for Electron Microscopy (CIME) at EPFL. Furthermore, we are  regular users of large facilities such as the National Synchrotron Light Source (BNL, USA), Swiss Light Source (Villigen), Paul Shaerrer Institute etc.

Low frequency ESR spectrometers

 

We have available ESR spectrometers operating at 4, 9 and 35 GHz with a standard 4-300 K cryostate (1st image). A special furnace allows measurements at 9 GHz up to 800°C (2nd). We have developed a high pressure (up to 2.5 GPa) and a stopped-flow options [1] (3rd and 4th) (development by: A. Sienkiewicz).

Very High frequency ESR spectrometer

           

 

We have developed a high frequency, continuous-wave ESR spectrometer with the following parameters: working frequency: 105, 210, 315, 420 GHz. power: ~1mW, magnetic field: 0-16 T,  quasioptical bridge, liquid He-cooled InSb bolometer, temperature range: 2-300 K (left panel), and hydrostatic pressure: up to 16 kbar [2] (right panel) (development by A. Janossy, T. Feher, B. Nafradi and R. Gaal).

L-band ESR spectrometer for MRI

 

The ESR spectrometer operating at 1 GHz is suitable for Magnetic Resonance Imaging of biological samples. The person responsable for running the experiment  is A. Sienkiewicz.

Photonic Force Microscope and AFM nanomanipulator

  

We have available 2 Photonic Force Microscopes (PFM) (an upgraded version of an optical tweezers) where the information is collected by following the Brownian motion of a bead (left image). The time and spatial resolutions are exceptional (1 µs and 2°A). The instrument was developed by Sylvia Jeney [3]. A heptic device adapted to an AFM allows manipulation (with real force feedback) at nanoscales (right image). The device was developed by M. Jobin, A. Kulik and R. Foschia [4] . The same approach was adopted to the PFM by E. Bertseva, J. Lekki,  A. Kulik  and S. Jeney [5].

Transport measurements under extreme conditions

   

The parameter space of magnetotransport measurements is: 40 mK -300 K, pressures up to 25 GPa and magnetic field up to 16 T (two left images). For the optical conductivity we have developed a high pressure cell operating up to 1.6 GPa down to the far infrared range (right image). This device was developed by R. Gaal [6] in collaboration with I. Kezsmarki (Technical University of Budapest) and tested at Brokhaven National Laboratories with L. Mihaly and Ch. Homes.

References:

[1] A. Sienkiewicz et al., Review of Scientific Instruments  65, 68-74  (1994). 

[2] B. Nafradi et al., Journal of Magnetic Resonance 192, 265 (2008).

[3] S. Jeney et al., Chemphyschem 5,1150-1158 (2004).

[4] M. Jobin et al., Rev. Sci. Instrum. 76, 053701 (2005)

[5] E. Bertseva et al, Nanotechnology 20, 285709 (2009). 

[6] I. Kezsmarki et al, Phys. Rev. B 76, 205114 (2007).