Measurement and control of detailed electronic properties in a single molecule break junction

2014 ◽  
Vol 174 ◽  
pp. 91-104 ◽  
Author(s):  
Kun Wang ◽  
Joseph Hamill ◽  
Jianfeng Zhou ◽  
Cunlan Guo ◽  
Bingqian Xu
Keyword(s):  
Data Analysis ◽  
Molecular Electronics ◽  
Single Molecule ◽  
Molecular Orbitals ◽  
Break Junction ◽  
Break Junctions ◽  
Single Molecule Level ◽  
Analysis Techniques ◽  
Future Design ◽  
Molecule Junction

The lack of detailed experimental controls has been one of the major obstacles hindering progress in molecular electronics. While large fluctuations have been occurring in the experimental data, specific details, related mechanisms, and data analysis techniques are in high demand to promote our physical understanding at the single-molecule level. A series of modulations we recently developed, based on traditional scanning probe microscopy break junctions (SPMBJs), have helped to discover significant properties in detail which are hidden in the contact interfaces of a single-molecule break junction (SMBJ). For example, in the past we have shown that the correlated force and conductance changes under the saw tooth modulation and stretch–hold mode of PZT movement revealed inherent differences in the contact geometries of a molecular junction. In this paper, using a bias-modulated SPMBJ and utilizing emerging data analysis techniques, we report on the measurement of the altered alignment of the HOMO of benzene molecules with changing the anchoring group which coupled the molecule to metal electrodes. Further calculations based on Landauer fitting and transition voltage spectroscopy (TVS) demonstrated the effects of modulated bias on the location of the frontier molecular orbitals. Understanding the alignment of the molecular orbitals with the Fermi level of the electrodes is essential for understanding the behaviour of SMBJs and for the future design of more complex devices. With these modulations and analysis techniques, fruitful information has been found about the nature of the metal–molecule junction, providing us insightful clues towards the next step for in-depth study.

scholarly journals Nearfield trapping increases lifetime of single-molecule junction by one order of magnitude

2020 ◽  
Author(s):  
Albert C. Aragonès ◽  
Katrin F. Domke
Keyword(s):  
Molecular Electronics ◽  
Single Molecule ◽  
Fold Increase ◽  
Trapping Efficiency ◽  
Non Invasive ◽  
Order Of Magnitude ◽  
Molecule Junction ◽  
Single Molecule Junction ◽  
The Difference ◽  
Power Densities

Abstract Progress in molecular electronics (ME) is largely based on improved understanding of the properties of single molecules (SM) trapped for seconds or longer to enable their detailed characterization. We present a plasmon-supported break-junction (PBJ) platform to significantly increase the lifetime of SM junctions of 1,4-benzendithiol (BDT) without the need for chemical modification of molecule or electrode. Moderate far-field power densities of ca. 11 mW/µm2 lead to a >10-fold increase in minimum lifetime compared to laser-OFF conditions. The nearfield trapping efficiency is twice as large for bridge-site contact compared to hollow-site geometry, which can be attributed to the difference in polarizability. Current measurements and tip-enhanced Raman spectra confirm that native structure and contact geometry of BDT are preserved during the PBJ experiment. By providing a non-invasive pathway to increase short lifetimes of SM junctions, PBJ is a valuable approach for ME, paving the way for improved SM sensing and recognition platforms.

scholarly journals Optical probes of molecules as nano-mechanical switches

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Dean Kos ◽  
Giuliana Di Martino ◽  
Alexandra Boehmke ◽  
Bart de Nijs ◽  
Dénes Berta ◽  
...  
Keyword(s):  
Molecular Electronics ◽  
Single Molecule ◽  
Electrical Transport ◽  
Density Functional ◽  
Information Technologies ◽  
Electronic Device ◽  
Density Functional Theory Calculations ◽  
Molecular Junction ◽  
Single Molecule Level ◽  
Ultralow Energy

AbstractMolecular electronics promises a new generation of ultralow-energy information technologies, based around functional molecular junctions. Here, we report optical probing that exploits a gold nanoparticle in a plasmonic nanocavity geometry used as one terminal of a well-defined molecular junction, deposited as a self-assembled molecular monolayer on flat gold. A conductive transparent cantilever electrically contacts individual nanoparticles while maintaining optical access to the molecular junction. Optical readout of molecular structure in the junction reveals ultralow-energy switching of ∼50 zJ, from a nano-electromechanical torsion spring at the single molecule level. Real-time Raman measurements show these electronic device characteristics are directly affected by this molecular torsion, which can be explained using a simple circuit model based on junction capacitances, confirmed by density functional theory calculations. This nanomechanical degree of freedom is normally invisible and ignored in electrical transport measurements but is vital to the design and exploitation of molecules as quantum-coherent electronic nanodevices.

Single-Molecule Junction Formation in Break-Junction Measurements

2021 ◽  
pp. 10802-10807
Author(s):  
Tianren Fu ◽  
Kathleen Frommer ◽  
Colin Nuckolls ◽  
Latha Venkataraman
Keyword(s):  
Single Molecule ◽  
Break Junction ◽  
Junction Formation ◽  
Molecule Junction ◽  
Single Molecule Junction

An electrochemically assisted mechanically controllable break junction approach for single molecule junction conductance measurements

Nano Research ◽  
2011 ◽  
Vol 4 (12) ◽  
pp. 1199-1207 ◽  
Author(s):  
Yang Yang ◽  
Zhaobin Chen ◽  
Junyang Liu ◽  
Miao Lu ◽  
Dezhi Yang ◽  
...  
Keyword(s):  
Single Molecule ◽  
Break Junction ◽  
Molecule Junction ◽  
Single Molecule Junction ◽  
Junction Conductance

Selective formation of molecular junctions with high and low conductance states by tuning the velocity of electrode displacement

2020 ◽  
Vol 22 (8) ◽  
pp. 4544-4548
Author(s):  
Yuji Isshiki ◽  
Shintaro Fujii ◽  
Tomoaki Nishino ◽  
Manabu Kiguchi
Keyword(s):  
Single Molecule ◽  
Molecular Junctions ◽  
Break Junction ◽  
Scanning Tunnelling ◽  
Electrode Displacement ◽  
Molecule Junction ◽  
Tunnelling Microscopy ◽  
Single Molecule Junction ◽  
Conductance States ◽  
Selective Formation

A single-molecule junction of 1,4-di(4-pyridyl)benzene (DPB) was prepared in a nano-gap between two Au electrodes using the scanning tunnelling microscopy-based break junction method (STM-BJ).

scholarly journals Long-lived charged states of single porphyrin-tape junctions under ambient conditions

2021 ◽  
Vol 6 (1) ◽  
pp. 49-58
Author(s):  
Edmund Leary ◽  
Georg Kastlunger ◽  
Bart Limburg ◽  
Laura Rincón-García ◽  
Juan Hurtado-Gallego ◽  
...  
Keyword(s):  
Charge State ◽  
Molecular Electronics ◽  
Single Molecule ◽  
Room Temperature ◽  
Ambient Conditions ◽  
Molecular Memory ◽  
Molecule Junction ◽  
Single Molecule Junction

Controlling the charge state of a molecule wired in a two-terminal single-molecule junction at room temperature is a key challenge in molecular electronics in relation to the development of molecular memory and other computational componentry.

scholarly journals Mechanical Conductance Tunability of a Porphyrin-Cyclophane Single-Molecule Junction

Nanoscale ◽  
2021 ◽  
Author(s):  
Werner M. Schosser ◽  
Chun-Wei Hsu ◽  
Patrick Zwick ◽  
Katawoura Beltako ◽  
Diana Dulic ◽  
...  
Keyword(s):  
Molecular Electronics ◽  
Single Molecule ◽  
Quantum Interference ◽  
Ambient Conditions ◽  
Molecule Junction ◽  
Single Molecule Junction

The possibility to study quantum interference phenomena at ambient conditions is an appealing feature of molecular electronics. By connecting two porphyrins in a cofacial cyclophane, we create an attractive platform...

scholarly journals Richness of molecular junction configurations revealed by tracking a full pull-push cycle

Nanoscale ◽  
2021 ◽  
Author(s):  
Tamar Yelin ◽  
Sudipto Chakrabarti ◽  
Ayelet Vilan ◽  
Oren Tal
Keyword(s):  
Molecular Electronics ◽  
Single Molecule ◽  
Electronic Transport ◽  
Molecular Orientation ◽  
Molecular Junction ◽  
Single Molecule Level ◽  
Central Interest

In the field of molecular electronics, the interplay between molecular orientation and the resulting electronic transport is of central interest. At the single molecule level, this topic is extensively studied...

Functional oligothiophenes toward molecular wires in single-molecular electronics

2012 ◽  
Vol 84 (4) ◽  
pp. 931-943 ◽  
Author(s):  
Yutaka Ie ◽  
Masaru Endou ◽  
Aihong Han ◽  
Ryo Yamada ◽  
Hirokazu Tada ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Molecular Electronics ◽  
Single Molecule ◽  
Scanning Tunneling Microscope ◽  
Molecular Wires ◽  
Scanning Tunneling ◽  
Tunneling Microscope ◽  
Molecule Junction ◽  
Single Molecule Junction ◽  
Cv Measurements

The synthesis of 3-hexylthiophene-based oligothiophenes with a length of approximately 10 nm bearing anchor units at both terminal positions has been accomplished. In addition, we have designed and synthesized completely encapsulated oligothiophenes to investigate single-molecule conductance. Their properties are evaluated by UV–vis absorption spectra and cyclic voltammetry (CV) measurements. The conductance of a single-molecule junction for thiol-introduced oligothiophenes was measured by 10-nm-scale nanogap gold electrodes or modified scanning tunneling microscope (STM) techniques.

On-Chip Break Junctions and Period-Adjustable Grating Driven by Thermal Stress

NANO ◽  
2017 ◽  
Vol 12 (11) ◽  
pp. 1750139 ◽  
Author(s):  
Ling Wang ◽  
Zhikai Zhao ◽  
Dong Xiang
Keyword(s):  
Single Molecule ◽  
Molecular Junctions ◽  
Molecular Devices ◽  
Break Junction ◽  
Gap Size ◽  
Break Junctions ◽  
Symmetrical Structure ◽  
Metal Grating ◽  
On Chip ◽  
First Time

The investigation of the electron transport through single molecule needs an efficient method to generate stable molecular junctions. There are various techniques, such as mechanically controllable break junction (MCBJ) technique and electromigration technique, to generate stable nanogaps and stable molecular junctions. However, it is a great challenge for MCBJ technique to obtain on-chip molecular junctions because of the constraint of the push rod components, which do not make it facile to fabricate highly integrated molecular devices. Meanwhile, the gap size between electrodes is nonadjustable for the electromigration method, which leads to a low yield of molecular junctions. In this report, a thermally controllable break junction method, which can overcome the above problem, is proposed for the first time. The device is based on a double-V-shaped symmetrical structure and mechanically driven by thermal expansion, thus the push rod is not needed. Furthermore, we proposed that the thermally controlled double-V-shaped structure can be employed to precisely adjust the period of the metal grating with nanometer accuracy, which is unavailable in other methods.

Sign in / Sign up

Export Citation Format

Share Document