Fig. 1: Current-voltage analysis of helicene molecular junctions under magnetic fields.
From: Single-molecule junctions map the interplay between electrons and chirality
a Illustration of chiral-induced spin selectivity (CISS). b Illustration of electrical magnetochiral anisotropy (EMCA). Here, the helix indicates a chiral conductor, red circles - electrons (e), red arrows—spin (S), blue arrows—electron transport directions, black arrows—magnetic field (B) directions. c Illustration of a break-junction setup and a helicene molecular junction. d Histogram and an average of current in absolute values as a function of voltage (\(\left|I\right|\)–V curves) for Ni(Au)/M-helicene/Au junctions under +2 T magnetic field, parallel to the junction. Ni(Au) refers to a Ni electrode wet by Au. e The same under −2 T magnetic field antiparallel to the junction. f Average of absolute value of current as a function of voltage for Ni(Au)/M-helicene/Au junctions under parallel and antiparallel +2 T and −2 T magnetic fields. g–i The same as (d–f) but for Ni(Au)/P-helicene/Au junctions. The standard error of the current [\(({{\rm{standard}}}\; {{\rm{deviation}}})/\sqrt{{{\rm{\#}}}\; {{\rm{of}}}\; {{\rm{curves}}}}\)] in (d) to (i) is smaller than the curve width. j Asymmetry as a function of voltage magnitude for Ni(Au)/M-helicene/Au junctions under the mentioned opposite magnetic fields. Asymmetry is defined as \({{\rm{Asymmetry}}}=100\cdot [\left|I(+V)\right|-\left|I\left(-V\right)\right|]/[\left|I\left(+V\right)\right|+\left|I\left(-V\right)\right|]\). k The same as in (j), but for Ni(Au)/P-helicene/Au junctions. The number of examined molecular junctions (and corresponding I–V curves) in each case varies between 251 to 377.
