the NMR group (established 2000): eguipment, NMR-people and topics - per September 2015 - a summary

members (per September 2015): H. Yasuoka (emeritus) M. Majumder (PostDoc)

target:
Ligand (³¹P, ^63,65Cu, ¹¹⁹Sn, ²³Na, ^99,101Ru, ²⁹Si, ¹³⁹La, ^121,123Sb, ⁷⁵As, ¹⁹⁵Pt) and on-site (¹⁷¹Yb, ⁵⁹Co, ⁵⁷Fe, ⁵⁵Mn,...) NMR-investigation of 4f-, 5f-, and d- intermetallics and oxides with unconventional magnetism and/or superconductivity.

The main targest are

i) correlated 4f- and 5f systems

ii) 3d based correlated systems

iii) Quantum magnets with main focus on SOC effects and non centrosymmetric structure (chiral magnets and 4d/5d quantum magnets) 

iiii) Dirac(Weyl) magnets: NMR as a local probe for Dirac (Weyl) fermion magnetism 

purpose:
NMR probes the local spin susceptibility at the NMR nucleus site via the NMR shift. The NMR shift is a tensor reflecting the local magnetic anisotropy at the nucleus site arising from anisotropic- (dipolar and orbital (p-,d- & f- electrons)) and isotropic- (Fermi contact (s electrons)) hyperfine interactions. The spin lattice relaxation rate probes fluctuations of the transfered hyperfine field originating from the (unstable) 4f-, 5f- or 3d magnetic ion (related to the q-dependent imaginary part of the complex dynamic susceptibility)

method:
Broadline field sweep NMR with a very broad range of accessible frequencies (1-500 MHz) enables multinuclear resonance (detection of various NMR sensitive nuclei with field sweeps up to 14 T).
Fourier Transform (FT) NMR.
High Resolution FT NMR (Bruker 400 MHz, Bruker 500MHz)
Temperatures avaiable: 2 K-700 K.

equipment:

-NMR spectrometer

        THREE Tecmag (Discovery/Apollo) 2 chanel NMR    
                       spectrometer (up to 1 GHz).
        ONE LapNMR Spectrometer (up to 125 MHz)
        ONE home build NMR/NQR spectrometer

-NMR probes
        VARIOUS home build solid state NMR probes       
                        with calibrated CERNOX temperature
                        sensors (design NMR SERVICE Dr.M. Braun)

-Magnets and cryostats 

         JANIS 9 T (9T-SVM-18) cold bore (KF40) 
                       10E-4  homogeneity magnet 
                       1.7 K - 300 K
         JANIS 14 T (14T-SVM-15) cold bore (KF40) 
                       10E-4 homogeneity magnet 
                       1.7 K - 300 K
         MAGNEX 9.2 T (10E-5 homogeneity) system
                       warm bore (8.9 cm) magnet plus
                       decoupled +-0.2 T modulation coil with
                       JANIS (STVP) He flow crostat
                       1.7 K - 400 K
         Bruker 400 MHz high resolution magnet (10E-9) plus
                       Oxford He flow cryostat and  
                       high temperature (700 K) probes plus
                       MAS probes.
         JANIS       He flow cryostat for NQR measurements