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The Laboratory of Electronic Kinetics (LEK) has powerful radio-frequency, microwave, cryogenic and high-magnetic-field sets of equipment, allowing to carry out precision phase-sensitive measurements of current and voltage in a frequency range 0-10 MHz and the microwave response of crystalline materials in cm-and mm- wavelength range in the temperature interval (0.1-300) K and in magnetic fields up to 18 T. Methodical principle of LEK development allows to investigate the same sample by different physical methods and to get the maximal information on its electron properties. Recently discovered transition from classical superconductivity to unusual one in crystals Ba1-xKxBiO3 can serve as a successful example of such approach [in more detail]. This effect was found by the measurements of temperature dependences of the upper critical field and a superconducting impedance: in crystals with Tc> 20 K (a and b in the left figure) temperature dependences of the upper critical field have positive curvature, and with Tc <15 K (c, d, e) are described by standard dependence; in full correlation with such behavior of a critical field the impedance of crystals below the critical temperature shows either linear or exponential (crystal c, the right Figure) behavior respectively.

During 2003-2007 years the Laboratory was equipped with the advanced and expensive measuring techniques. Developed and tested in LEK the superconducting solenoid with a magnetic field as high as 18 T at T=4.2 K, and cryogenic systems (the Patent N 46084 "Low-temperature insert for the cryostat with pumping out of He3 vapor for operation in a range (0.3-300) K ") is in active demand of researchers both from our country and from abroad. This is confirmed by the fact that more than 10 treatments, utilizing the LEK equipment for scientific and technical collaboration with universities, institutes of the Russian Academy of Sciences (RAS) and scientific research institutes of the Russian Federation, were arranged within last several years. For the period 2002-2006 LEK's cryo system has been made (duplicated) for 5 institutes of the RAS: Institute of Metal Physics Ural Division, Institute of Semiconductor Physics Siberian Branch of RAS, Institute of Radioengineering and Electronics, Institute of Microelectronics Technology and High-Purity Materials, Lebedev Physical Institute; special low-temperature microwave equipment on the basis of the gold 9.3 GHz frequency resonator has been made for the University of Palermo (Italy). During this period several scientists from abroad worked in LEK: Italian researchers from the University of Palermo (more than half a year), the scientific researcher from Baku Institute of Physics (Azerbaijan) (about one year), and also employees (each during the month) from the Institute of Radioengineering and Electronics of RAS, Institute of Semiconductor Physics Siberian Branch of RAS, Institute of Metal Physics Ural Division of RAS, Institute of Inorganic Chemistry Siberian Branch of RAS and Institute of Problems of Chemical Physics of RAS. As a result of this collaboration 10 papers with participation of researchers from Russian and foreign scientific institutions in 2004-2006 were published in leading scientific journals. LEK's equipment is permanently used by students and post-graduate students of the Solid state physics faculty of Moscow Institute of Physics and Technology for scientific researches.

The Laboratory steadily expands its methodical opportunities. The works are started on:

  • creation of the universal microwave setup for studies of high-frequency properties of samples in a millimeter range of wavelengths from room down to ultra-low temperatures and in magnetic fields up to 18 T
  • improvement of cryosystems for more easy access to the liquid He3 volume (T=0.3 K) for various, including comparatively bulky devices (systems for sample rotation, wave guides, optical paths, etc.)
  • development of the original dilution refrigerator for low (down to 50 mK) temperatures
  • the creation of a method for measurements of shot noise of a current in mesoscopic bridges at high temperatures when the thermal noise prevails.
  • development of non-resonant spectral method of refraction factor measurements in metamaterials in the frequency range from 0.1 up to 40 GHz

Equipment complexes for the studies of electromagnetic properties of new materials include:


The automated equipment for the low-frequency measurements of semiconductor, metal and superconductor conductivity allowing to study:

  • Temperature dependences of sample resistance in a temperature range (0.3 - 300) K. The four-contact measurement technique is developed for studying the anisotropic samples (high - temperature superconductors, organic metals, layered semiconductors), allowing to define both resistance anisotropy and the components of the resistivity tensor on the samples with the size as small as 0.2 mm.
    Inserts for the express measurements in liquid helium Dewar in the temperature range (4.2 - 300) K.
  • Magneto resistance of the normal metal and semiconductor samples as well as the temperature dependences and the anisotropy of the upper critical field in superconductors in the temperature range (0.3 - 300) K and in magnetic fields up to 18 T. The cryostats with superconducting solenoids and the inserts with He3 pumping out are used for such measurements.

A sample with the size of 0.2 mm
The four-contact measurement technique

For the listed measurements the high-sensitivity equipment operated by computers on the basis of modern Lock-in amplifiers SR and PAR and digital multimeters Agilent and Solartron is used


Cryostats and solenoids

Typical cryostat with 14 T solenoid

The superconducting solenoid developing a stationary magnetic field 18 T at liquid helium temperature T = 4.2 K


Low temperature devices
Original cryosystem for precision sample conductivity and dynamic susceptibility measurements in the frequency range from 10 Hz up to 10 MHz at the temperatures (0.3-300) K in a magnetic fields up to 8, 12, 14 and 18 T, created by superconducting solenoids
Original microwave devices for precision temperature dependence measurements (from 0.4 K up to 200 K) of real and imaginary parts of a surface impedance of the samples in cm- and mm- ranges of wavelengths
Original dilution refrigerator for the measurements at ultra low (down to 50 mK) temperatures in strong magnetic fields, created by superconducting solenoids


The automated setup for the express measurements of a dynamic magnetic susceptibility of the samples in a temperature range (2 - 300) K

  • Sensitivity 10-9 emu
  • An alternative magnetic field amplitude (0.1-10) Oe
  • Frequency of an alternative field - up to 10 MHz
  • Magnetic field up to 18 T
  • The characteristic feature of the setup is that electromagnetic coils are immersed into a liquid helium (T = 4.2 K) during the measurements of susceptibility temperature dependences, which provides high stability of the amplification factor


Microwave setups
The original microwave setups allowing to carry out precise temperature dependence measurements of real R (T) and imaginary X (T) parts of the surface impedance Z (T) on the samples of the small size (the surface area about one square millimeter) in centimeter and millimeter ranges of wavelengths. These setups include two basic elements: super high-stable generators of Agilent Technologies Company (USA) with 0.01 Hz frequency resolution in a frequency range from 200 KHz up to 40 GHz and low-temperature high-vacuum devices on the basis of superconducting Nb resonators with good quality factor at T= 2 K, greater than 10 and 2 millions on the frequencies 10 and 30 GHz respectively. Surface resistance R (T) of the sample is measured with accuracy about 1 mikro Ohm and electromagnetic field penetration depth in the sample with an error smaller then 5 nm. Now these parameters are the best in the world.   Experimentally obtained values R (T) and X (T) in absolute units (Ohms) for different orientations of the sample with respect to a microwave field in the resonator allow to find the components of the complex conductivity - the main electrodynamical characteristic of the sample, both in normal (up to T= 300 K), and in superconducting (down to T= 0.4 K) states of the investigated sample.
The original setup for studies of microwave properties of dielectric films and their cap-layers in a range of frequencies from 25 up to 40 GHz, allowing to measure:


  • dielectric permeability of the films with the thickness from 50 microns to 1 mm in the permeability range from 2 to 1
  • loss tangent of dielectric films in an interval from 0.1 to 0.0001
  • microwave conductivity and a surface impedance of the copper film, measured from dielectric substrate side
  • temperature dependences of all specified above characteristics in an interval from -60 C up to +70 C

142432, Chernogolovka, Moscow district, Russia