Hybrid molecular devices

Silicon is a material of major technological importance since it forms the basis of a vast range of electronic devices such as transistors, microprocessors and solar cells. It is also likely to be used in numerous future technologies including atomic scale devices [17,18], ultra dense storage devices [19], quantum computers [20,21] and hybrid molecular devices [22]. The surfaces of silicon are the most thoroughly studied of all semiconductor surfaces and there are numerous known surface reconstructions [23]. In this section we... 

Photons in quantum optical cavities also constitute excellent qubit candidates [52]. Resonant coupling of atoms with a single mode of the radiation field was experimentally achieved 25 years ago [53], and eventually the coherent coupling of quantum optical cavities with atoms or (simple) molecules was suggested as a means to achieve stable quantum memories in a hybrid quantum processor [54]. There might be a role to play for molecular spin qubits in this kind of hybrid quantum devices that combine solid-state with flying qubits. 

Joachim C, Gimzewski JK, Aviram A (2000) Electronics using hybrid-molecular and mono-molecular devices. Nature 408(6812) 541-548... 

Moons E, Bruening M, Shanzer A, Beier J, Cahen D (1996) Electron transfer in hybrid molecular solid-state devices. Synth Met 76 245-248... 

Towards fabrication of SWNT-based molecular electronic devices, two methods have been used to assemble the 03-SWNTs on functionalized SAMs of OPEs, as shown in Figure 5.10. The first, termed chemical assembly , is based on a condensation reaction between the carboxylic acid functionalities of O3-SWNTs and the amine functionalities of SAMs to form amides. The results show that O3 -SWNTs coat the amino-terminated SAM with a high degree of surface coverage. The second method is based on physical adsorption via layer-by-layer (LBL) deposition with bridging of metal cations, i.e., Fe3+ on carboxylate terminated SAMs or Cu2+ on thiol-terminated SAMs. The oxidatively shortened 03 -SWNTs are shown to be perpendicular to the surface with random adsorption of longer tubes. The patterned nanotube assemblies may be useful in hybridized electronic devices, where device functions can be modified by the orientation and stacking of SWNTs, and the properties of the SAM. 

From this comparison it can be concluded that on the device level there are fundamental limits for the miniaturization of hybrid-molecular electronics, which are not only governed by the size of the molecule but also depend on the size that an electromechanical or capacitative grid has to have in order to influence its energy levels. These architectural issues regarding the interfacing of a molecular device to the outside world or the assembly of many devices into larger circuits will have to be addressed to a larger extent in the near future. 

Coronado, E. and Palomares, E. Hybrid molecular materials for optoelectronic devices, J. Mater. Chem., 2005, 15, 3593-3597. 

C. Joachim, J.K. Gimzewski, A. Aviram, Electronics Using Hybrid-Molecular and Mono-Molecular Devices , Nature, 408,541 (2000)... 

Kruger J, Bach U, Gratzel M (2000) Modification of Ti02 heterojunctions with benzoic acid derivatives in hybrid molecular solid-state devices. Adv Mater 12 447... 

J. Kruger, U. Bach, M. Gratzel, Modification of Ti02 Heterojunctions with Benzoic Acid Derivatives in Hybrid Molecular Solid-State Devices, Adv. Mater. 2000, 12, 447-451. 

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