Layout of the UHV recipient with (1) the cryostat chamber, (2) the preparation chamber, (3) liquid nitrogen bath cryostat, (4) liquid helium bath cryostat, (5) Joule-Thomson cryostat, and (6) microscope head.
Scheme of the cryostat. (1) Liquid nitrogen tank, (2) liquid helium tank, (3) in and out let of liquid helium, (4) in and out let of 3He, (5) countercurrent heat exchanger for 3He, (6) radiation shield, (7) heat exchangers coupled with cryogenic gas, (8) superconductive coil, and (9) microscope head.
Schematics of the 3He cycle in Joule-Thomson cooling stage.
Temperature of (a) the STM head and (b) the Joule-Thomson cryostat as a function of time after starting the Joule-Thomson expansion of 4He.
Temperature of the STM head as a function of time after starting the Joule-Thomson expansion of 3He–4He mixture.
Schematics of STM head, (1) sample rack, (2) sample and sample plate, (3) piezo for coarse motion in x-direction, (4) tip and scanner, (5) scanner-holder (Cu prism), and (6) piezo for coarse motion in z-direction.
Process of tip transfer in four steps using a special sample plate and coarse motion in x and z directions.
(a) Scheme of the superconducting split-coil magnet, (1) split-coil made of NbTi wire, (2) coil body, (3) STM head, (4) Cu posts as thermal anchoring between magnet and 4.2 K bath cryostat, which also support the coil body and carry the current for the coil back to ground, (5) 4.2 K bath cryostat, and (6) 3He pot of Joule-Thomson cryostat. (b) Calculated deformations of the coil body when the coil generates a magnetic field of 3 T.
Calculated field distribution inside the split-coil magnet, (1) split coils, (2) sample, and (3) STM head.
Atomic resolution of Cu(100) at 930 mK. (a) Topography of Cu(100), (b) line section along L1, (c) and L2.
Noise power spectrum of tunneling current at 1.1 K (a) with the liquid nitrogen bath fully filled and (b) with frozen nitrogen.
(a) A topography of the herringbone reconstruction on the Au(111) surface,31 (b) line section of (a) which demonstrates a z-noise of about 200 fm.
(a) Topography of Au(111) recorded at 1.1 K with a tunneling current of 1 pA and a sample bias of 1 mV. (b) STS measurement with a set point of 4 pA on a organic molecule adsorbed on Au(111) ramping the voltage up (soild line) and down (dashed line).
(a) Current noise power of retracted tip (dashed line) and in tunneling with turned off feedback loop (solid line). (b) Distance dependence of tunneling current I(d). (c) Extracted vibration noise power.
STM images of the same atom demonstrating no observable lateral drift (<20 pm/h) after STM head reached at 1.1 K. The drift was only 0.9 nm when STM was cooled down form 4.5 K to 1.1 K.
(a) Topography and (b) dI2/d2V map of Nb(110) obtained at 1.1 K and a magnetic field of 0.21 T with a bias of U = 1.2mV. The flux vortices were clearly resolved in the map of the quasiparticle density.
(a) STS of Nb tip on Cu(100), dotted line: experimental data; dashed line: fitting curve with a fit temperature of 1.15 K reproducing the energy gap; solid line: fitting curve with a fit temperature of 650 mK reproducing the quasiparticle states. (b) Inelastic signal from the phonon excitation of CO on Au(111).
Article metrics loading...
Full text loading...