Unveiling the nature of atomic defects in graphene on a metal surface

• Karl Rothe,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2024, 15, 416–425, doi:10.3762/bjnano.15.37

• intact graphene sheet. Spatially resolved spectroscopy of the differential conductance and the measurement of total-force variations as a function of the lateral and vertical probe–defect distance corroborate the different character of the defects. The tendency of the vacancy defect to form a chemical

• are indeed lacking the graphene atomic lattice structure in their interior. Spatially resolved spectroscopy of the differential conductance (dI/dV, I: tunneling current, V: bias voltage) and of the tuning fork resonance frequency change (Δf) further unravel marked differences between these two kinds

Molecular nanoarchitectonics: unification of nanotechnology and molecular/materials science

• Katsuhiko Ariga

Beilstein J. Nanotechnol. 2023, 14, 434–453, doi:10.3762/bjnano.14.35

• intermediates, and the final product were identified in situ by differential conductance imaging using a CO-modified tip. The bias voltage was set above the lowest unoccupied molecular orbital energy and the probe was placed over the C–Br bond, which was then broken. After the reaction, a dip appeared on the

• remove the second bromine atom. Close-up observation of the structure showed that the molecule was fully debrominated. Differential conductance imaging confirmed that the molecular skeleton, including the two naphthalene moieties, was clearly resolved. It was also observed that the two naphthalene

Observation of collective excitation of surface plasmon resonances in large Josephson junction arrays

• Roger Cattaneo,
• Mikhail A. Galin and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2022, 13, 1578–1588, doi:10.3762/bjnano.13.132

• not seen for smaller N. To quantify the step amplitude, ΔI, at small N we plot the differential conductance, dI/dV. Figure 5b shows the dI/dV(I) curves for the I–Vs from Figure 5a, normalized by the resonant voltage Vstep. This quantity does not depend on the number of active JJs. A current step in

• array at the main resonance. Figure 8b shows the step amplitude as a function of the number of active JJs for this resonance. Blue symbols represent ΔI measured directly from the I–V characteristics. Orange symbols are obtained by integration of the areas of the peak in differential conductance, taken

• and gradual evolution of several steps with increasing N. Edges of three distinct resonant steps are indicated by dashed green lines. (a) Parts of the V–I curves near the main resonance for the meander array with different number of active JJs, N. (b) Normalized differential conductance for the I–V

Experimental and theoretical study of field-dependent spin splitting at ferromagnetic insulator–superconductor interfaces

• Peter Machon,
• Michael J. Wolf,
• Detlef Beckmann and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2022, 13, 682–688, doi:10.3762/bjnano.13.60

• from a first-order to a second-order phase transition for large spin mixing angles. The experimentally found differential conductance of an EuS-Al heterostructure is compared with the theoretical calculation. With the assumption of a uniform spin mixing angle that depends on the externally applied

• an oxide layer. The normal layer acts as the tunnel probe to measure the differential conductance of the superconductor and is assumed not to influence the system properties. Since the size of the detector electrode is not small (unlike the tip of a scanning tunneling microscope) and the FI affects

• a Si(111) substrate heated to 800 °C. In a second fabrication step, aluminium/aluminium oxide/copper tunnel junctions were fabricated on the EuS film using e-beam lithography and shadow evaporation. The nominal aluminium film thickness was d = 10 nm. The differential conductance g = dI/dV of the

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• = 3.7 V) STM topography of h-BN/Cu(111) and the bare Cu(111) surface. Blue circles and red rings mark exemplary valley and rim areas, respectively. (c.) Differential conductance dI/dV spectra taken at rim (red line) and valley (blue line) sites and at the bare Cu(111) substrate (dashed black line). STM

• /AFM characterisation of a h-BN/Cu(111) Moiré superstructure. (a., b.) Constant-current topography at I = 500 pA and V = 3.6 V (top) or V = 5 mV (bottom). (c., d.) Simultaneously measured differential conductance (dI/dV) maps (Vmod = 10 mV (top) and Vmod = 1 mV (bottom). (e., f.) Frequency shift (Δf

Self-assembly and spectroscopic fingerprints of photoactive pyrenyl tectons on hBN/Cu(111)

• Domenik M. Zimmermann,
• Knud Seufert,
• Luka Ðorđević,
• Tobias Hoh,
• Sushobhan Joshi,
• Tomas Marangoni,
• Davide Bonifazi and
• Willi Auwärter

Beilstein J. Nanotechnol. 2020, 11, 1470–1483, doi:10.3762/bjnano.11.130

• sample being held at ≈6 K using electrochemically etched W tips. In the figure captions, voltages refer to the bias voltage applied to the sample. Differential conductance (dI/dV) spectra were recorded using the lock-in technique (f = 969 Hz, Vrms= 18 mV). Reducing the tip-sample distance by increasing

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

• Karl Rothe,
• Alexander Mehler,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

• -covered Ir(111) [9] have been reported so far. In these studies molecular orbitals, the highest occupied molecular orbital (HOMO) or the lowest unoccupied molecular orbital (LUMO), appear with spectroscopic fine structure in differential conductance (dI/dV, I: tunneling current, V: bias voltage) data

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• 4.6 K. Differential conductance (dI/dV) maps and spectra were recorded with a lock-in amplifier at modulation frequencies of 812–921 Hz, with the amplitudes given in the figure captions. Characterization of single-layer MoS2 on Ag(111) Figure 1a presents an STM image of the Ag(111) surface after the

• moiré pattern bears a topographic and an electronic modulation [38], we investigate the differential conductance (dI/dV) spectra on different locations (Figure 1d). We first examine the spectrum on the top site of the moiré structure. We observe a gap in the density of states, which is flanked by an

Nonequilibrium Kondo effect in a graphene-coupled quantum dot in the presence of a magnetic field

• Levente Máthé and
• Ioan Grosu

Beilstein J. Nanotechnol. 2020, 11, 225–239, doi:10.3762/bjnano.11.17

• does not show up in the density of states and in the differential conductance for zero chemical potential due to the linear energy dispersion of graphene. An analytical method to calculate self-energies is also developed which can be useful in the study of graphene-based systems. Conclusion: Our

• , to the right for spin-up electrons and to the left for spin-down electrons. Thus, the Kondo peaks originally located at the values of the chemical potentials are split into two new peaks. It was found that the differential conductance consists of an observable peak when the asymmetric bias voltage

• the Kondo temperature showing similar behavior to previous works. The corresponding DOS and differential conductance are also examined. The paper is organized as follows. First, we introduce the model and determine the Green’s function of the QD using the EOM method. Then, we derive formulas for the

Molecular attachment to a microscope tip: inelastic tunneling, Kondo screening, and thermopower

• Rouzhaji Tuerhong,
• Mauro Boero and
• Jean-Pierre Bucher

Beilstein J. Nanotechnol. 2019, 10, 1243–1250, doi:10.3762/bjnano.10.124

• in the gap of the STM is investigated by probing the differential conductance through the junction. The STS spectrum of a MnPc molecule flat-lying on Au(111) is taken with a bare metallic tip and used as a reference spectrum to be compared with the STS result obtained with a MnPc-terminated tip

• spectroscopy (IETS) close to the Fermi level. The differential conductance (dI/dV) spectrum (Figure 2e) reveals a prominent sharp peak close to the zero-bias voltage and two side peaks corresponding to step-like increases in the dI/dV signal (labeled ΔG) at threshold voltages |Vth| = 110 ± 5 meV. This is a

• surprising since is too small to produce any smearing of the Kondo resonance [36]. The Seebeck coefficient S can be calculated from the dI/dV data as a function of the temperature, obtained at constant height with an open feedback loop [37]: where σ(V) is the differential conductance and Σ(V) is its

Transport signatures of an Andreev molecule in a quantum dot–superconductor–quantum dot setup

• Zoltán Scherübl,
• András Pályi and
• Szabolcs Csonka

Beilstein J. Nanotechnol. 2019, 10, 363–378, doi:10.3762/bjnano.10.36

• superconductor tunnel-coupled to the dots, often called a Cooper-pair splitter. We study the three special cases where one of the three non-local mechanisms dominates, and calculate measurable ground-state properties, as well as the zero-bias and finite-bias differential conductance characterizing electron

• associated negative differential conductance in the Cooper-pair splitter, and show that they can arise regardless of the nature of the dominant non-local coupling mechanism. Our results should facilitate the characterization of hybrid devices, and their optimization for various quantum-information-related

• lead and the QD–SC–QD system, therefore connects states with different fermion parities. The differential conductance of lead Nα is calculated by numerically differentiating the current by the chemical potential of the normal leads, i.e., We plot the conductance in the units of the conductance quantum

Apparent tunneling barrier height and local work function of atomic arrays

• Neda Noei,
• Alexander Weismann and
• Richard Berndt

Beilstein J. Nanotechnol. 2018, 9, 3048–3052, doi:10.3762/bjnano.9.283

• topographs and from a characteristic signature in differential conductance (dI/dV) spectra. As first reported by Fölsch et al., short single-atom Cu chains on Cu(111) exhibit an unoccupied resonance at 1.5 eV above the Fermi energy EF [36]. Closely related data including the limit of very long chains were

Electronic conduction during the formation stages of a single-molecule junction

• Atindra Nath Pal,
• Tal Klein,
• Ayelet Vilan and
• Oren Tal

Beilstein J. Nanotechnol. 2018, 9, 1471–1477, doi:10.3762/bjnano.9.138

• to the vibration energy and its height is equal to the inelastic conductance contribution to the overall conductance across the junction. Figure 2a shows a differential conductance curve (dI/dV vs V) taken across a Ag–vanadocene junction with a zero-voltage conductance of ≈0.6 G0. The observed

• ) junctions. The traces are shifted for clarity. (a) Differential conductance vs applied voltage (dI/dV vs V) spectra measured at ≈0.6 G0 zero-voltage conductance after the introduction of vanadocene to the Ag junction. The steps in the conductance curve that are considered in the text are marked by arrows

Interplay between pairing and correlations in spin-polarized bound states

• Szczepan Głodzik,
• Aksel Kobiałka,
• Anna Gorczyca-Goraj,
• Andrzej Ptok,
• Grzegorz Górski,
• Maciej M. Maśka and
• Tadeusz Domański

Beilstein J. Nanotechnol. 2018, 9, 1370–1380, doi:10.3762/bjnano.9.129

• Green’s functions can be computed numerically from the solution of the Bogoliubov–de Gennes equations of this model (Equation 10). The net spin current turns out to be predominantly sensitive to the Majorana end-modes. Its differential conductance can thus distinguish the polarized Majorana

Disorder-induced suppression of the zero-bias conductance peak splitting in topological superconducting nanowires

• Jun-Tong Ren,
• Hai-Feng Lü,
• Sha-Sha Ke,
• Yong Guo and
• Huai-Wu Zhang

Beilstein J. Nanotechnol. 2018, 9, 1358–1369, doi:10.3762/bjnano.9.128

• different interactions in the system. Numerical results In this section we present the numerical results of the transport properties for the disordered Majorana nanowire. Here we mainly discuss the disorder-induced effects on the differential conductance, especially on the conductance peak spacing and its

• remove the peak spacing in the differential conductance and induce a zero-bias peak for a finite Majorana energy splitting. For a shorter nanowire, the magnitude of the conductance peaks and the peak spacings are considerably suppressed as the disorder is taken into account. Such a disorder-induced

• differential conductance G = dI/dV as a function of the bias voltage V under the influence of different types of disorder. (a,d) disorder δμ in the chemical potential; (b,e) disorder δt in the nearest hopping; (c,f) disorder δΔ in pairing energy. The upper panels corresponds to the shorter wire case L = 0.6 μm

Revealing the interference effect of Majorana fermions in a topological Josephson junction

• Jie Liu,
• Tiantian Yu and
• Juntao Song

Beilstein J. Nanotechnol. 2018, 9, 520–529, doi:10.3762/bjnano.9.50

• ) Flux-dependent DOS of the electron part (red solid line) and the hole part (blue solid line) along the energy spectrum in panel (d). They are not correlated with each other. Two STM leads (or weak coupled normal leads) localized at the junction can read the putative 4π period through the differential

• conductance. (a) Contour plot of the Andreev reflection coefficient TA of a STM lead as a function of the flux and the incident energy E. (b) Contour plot of the electron tunneling coefficient Te from the STM lead 1 to the STM lead 2 as function of the flux and the incident energy E. (c) The ratio between

Inelastic electron tunneling spectroscopy of difurylethene-based photochromic single-molecule junctions

• Youngsang Kim,
• Safa G. Bahoosh,
• Dmytro Sysoiev,
• Thomas Huhn,
• Fabian Pauly and
• Elke Scheer

Beilstein J. Nanotechnol. 2017, 8, 2606–2614, doi:10.3762/bjnano.8.261

• the lock-in technique [15][19][20]. In this study, the second derivative (d2I/dV2) is measured simultaneously with the differential conductance (dI/dV) by means of two lock-in amplifiers. The second derivative is normalized with dI/dV to compensate for the conductance change. Thus the IET spectroscopy

Transport characteristics of a silicene nanoribbon on Ag(110)

• Ryoichi Hiraoka,
• Chun-Liang Lin,
• Kotaro Nakamura,
• Ryo Nagao,
• Maki Kawai,
• Ryuichi Arafune and
• Noriaki Takagi

Beilstein J. Nanotechnol. 2017, 8, 1699–1704, doi:10.3762/bjnano.8.170

• nanojunction consisting of tip, SiNR and Ag is fabricated. In the differential conductance spectra of the nanojunctions fabricated by this methodology, a peak appears at the Fermi level which is not observed in the spectra measured either for the SiNRs before being lifted up or the clean Ag substrate. We

• SiNR from the substrate electronic system and elucidate the intrinsic properties. We measure the differential conductance (dI/dV) spectra of the nanojunctions and find a sharp peak structure at the Fermi level. Results and Discussion Figure 1a shows a topographic STM image of the Ag(110) surface after

• the electrically heated Si wafer. The Ag(110) substrate was heated at 500 K during the Si deposition. The deposition rate was 0.03 ML/min, where 1 ML ≈ 1.5 × 1015 Si atoms/cm2. The differential conductance spectra (dI/dV) were measured by a lock-in technique with the modulation voltage of 0.4–8.0 mV

Adsorption and electronic properties of pentacene on thin dielectric decoupling layers

• Sebastian Koslowski,
• Daniel Rosenblatt,
• Alexander Kabakchiev,
• Klaus Kuhnke,
• Klaus Kern and
• Uta Schlickum

Beilstein J. Nanotechnol. 2017, 8, 1388–1395, doi:10.3762/bjnano.8.140

• the pentacene molecules were probed by measuring the differential conductance (dI/dV) in STS experiments. In STS, pentacene reveals two molecular orbitals near the Fermi energy of the substrate, one at negative (−2.1 V) and one at positive bias voltage (+1.2 V) (Figure 2). The absolute peak positions

• . During STM, all bias voltages were applied with respect to the sample, meaning that for negative bias voltages, electrons tunnel from the sample to the tip. For STS measurements, the differential conductance was recorded utilizing a lock-in amplifier. The bias voltage was modulated with an amplitude of

Adsorption characteristics of Er₃N@C₈₀on W(110) and Au(111) studied via scanning tunneling microscopy and spectroscopy

• Sebastian Schimmel,
• Zhixiang Sun,
• Danny Baumann,
• Denis Krylov,
• Nataliya Samoylova,
• Alexey Popov,
• Bernd Büchner and
• Christian Hess

Beilstein J. Nanotechnol. 2017, 8, 1127–1134, doi:10.3762/bjnano.8.114

• -monolayer (bright half), the slightly visible interfacial reconstruction and the bare Au(111)-surface (dark half) can be seen. Interestingly, as illustrated in Figure 5b and c, spatial variations of the electronic structure occurred. The corresponding differential conductance maps (Figure 5b,c) respectively

Solvent-mediated conductance increase of dodecanethiol-stabilized gold nanoparticle monolayers

• Patrick A. Reissner,
• Jean-Nicolas Tisserant,
• Antoni Sánchez-Ferrer,
• Raffaele Mezzenga and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2016, 7, 2057–2064, doi:10.3762/bjnano.7.196

• conductance of such devices was measured by acquiring I–V curves before and after immersing them in pure solvents. All devices exhibit a linear current–voltage response before and after solvent immersion as shown in Figure 1a for a randomly picked device. The differential conductance value of each device is

Nonlinear thermoelectric effects in high-field superconductor-ferromagnet tunnel junctions

• Stefan Kolenda,
• Peter Machon,
• Detlef Beckmann and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2016, 7, 1579–1585, doi:10.3762/bjnano.7.152

• dependence of TF on Iheat by measuring the differential conductance of the junction while applying a dc heater current. The actual temperature difference δT is usually slightly smaller than δTF = TF − T obtained from the calibration measurements due to indirect heating of the superconductor. We typically

Charge and heat transport in soft nanosystems in the presence of time-dependent perturbations

• Alberto Nocera,
• Carmine Antonio Perroni,
• Vincenzo Marigliano Ramaglia and
• Vittorio Cataudella

Beilstein J. Nanotechnol. 2016, 7, 439–464, doi:10.3762/bjnano.7.39

• consequence, intriguing nonlinear phenomena, such as hysteresis, switching, and negative differential conductance have been observed in molecular junctions. In conducting molecules, either the center of mass oscillations [9], or thermally induced acoustic phonons [10] can be the source of coupling between

Probing the local environment of a single OPE3 molecule using inelastic tunneling electron spectroscopy

• Riccardo Frisenda,
• Mickael L. Perrin and
• Herre S. J. van der Zant

Beilstein J. Nanotechnol. 2015, 6, 2477–2484, doi:10.3762/bjnano.6.257

• become more evident when looking at the differential conductance (dI/dV) or the d2I/dV2, where they show up as steps, or peaks (dips), respectively. In this manuscript, when dealing with experimental data, we call IETS spectra the d2I/dV2/(dI/dV) signals calculated from the IV characteristics. Here, we

Effects of spin–orbit coupling and many-body correlations in STM transport through copper phthalocyanine

• Benjamin Siegert,
• Andrea Donarini and
• Milena Grifoni

Beilstein J. Nanotechnol. 2015, 6, 2452–2462, doi:10.3762/bjnano.6.254

• experimental measurements of 21 meV [8]. Numerical results for the current and the differential conductance, according to Equation 37 and using the full Hamiltonian in Equation 29, are shown in Figure 4. Anionic (cationic) resonances at positive (negative) bias voltages are clearly seen. Notice that, in our

• considerations yielded αT = 0.59 for the tip and αS = −0.16 for the substrate [11]. If given without indices, Vres denotes the bias voltage corresponding to the groundstate-to-groundstate resonance. The negative differential conductance at large negative bias in Figure 4 is caused by blocking due to population

• master equation for the reduced density matrix associated to the full many-body Hamiltonian had to be solved in order to numerically obtain both the current and the differential conductance. Noticeably, by using the effective spin Hamiltonian, it was possible to reconstruct the nature of the many-body