Ultrafast atomic-scale scanning tunnelling spectroscopy of a single vacancy in a monolayer crystal

Defects in atomically thin semiconductors and their moiré heterostructures have emerged as a unique testbed for quantum science. Strong light–matter coupling, large spin–orbit interaction and enhanced Coulomb correlations facilitate a spin–photon interface for future qubit operations and efficient single-photon quantum emitters. Yet, directly observing the relevant interplay of the electronic structure of a single defect with other microscopic elementary excitations on their intrinsic length, time and energy scales remained a long-held dream. Here we directly resolve in space, time and energy how a spin–orbit-split energy level of an isolated selenium vacancy in a moiré-distorted WSe2 monolayer evolves under the controlled excitation of lattice vibrations, using lightwave scanning tunnelling microscopy and spectroscopy. By locally launching a phonon oscillation and taking ultrafast energy-resolved snapshots of the vacancy’s states faster than the vibration period, we directly measure the impact of electron–phonon coupling in an isolated single-atom defect. The combination of atomic spatial, sub-picosecond temporal and millielectronvolt energy resolution marks a disruptive development towards a comprehensive understanding of complex quantum materials, where the key microscopic elementary interactions can now be disentangled, one by one

Influence of genetic variants of kappa casein on rheological milk properties

Elektroforetskim razdvajanjem bjelančevina mlijeka u alkalnom škrobnom gelu identificirali smo genotip kapa kazeina za 117 krava sivosmeđe pasmine. Osim genetskih varijanata A i B, na kapa kazeinskom lokusu našli smo i varijantu C. Proučavali smo utjecaj genotipa kapa kazeina na koagulacijska svojstva mlijeka, postotak bjelančevina u mlijeku i postotak mliječne masti. Utjecaj genotipa kapa kazeina bio je visoko signifikantan na čvrstoću gruša (a30). Izračunali smo regresijske koeficijente koagulacionih svojstava r, K20 i a30 za postotak proteina u mlijeku i postotak mliječne masti.Kappa casein genotypes were identified for 117 Brown cows using alkaline starch gel electrophoresis. In addition to genetic variants A and B the third variant C was found on the kappa casein locus. The influence of kappa casein genotype on coagulation properties of milk, and protein and fat percentage was studied. The influence of kappa casein genotype on curd firmness (a30) was highly significant. The regression coefficients for the properties r, K20 and a30 on protein and fat percentage in milk were calculated