Development of a molecular gap-type atomic switch and its stochastic operation

The gap-type atomic switch is a novel neuromorphic device that possesses functions such as analog changes in resistance and short-term/long-term memory-based learning. However, it is difficult to integrate conventional gap-type atomic switches that use a vacuum gap and Ag2+δS, which has restricted their practical use. In this study, we developed a new, easy to fabricate gap-type atomic switch that incorporates a molecular layer as a gap and Ta2O5 as an ionic transfer material. This molecular gap-type atomic switch operates in a manner that is similar to conventional vacuum gap-type atomic switches. We also demonstrate stochastic operations using the aforementioned molecular gap-type atomic switches. These results indicate a higher potential for the practical use of gap-type atomic switches.The gap-type atomic switch is a novel neuromorphic device that possesses functions such as analog changes in resistance and short-term/long-term memory-based learning. However, it is difficult to integrate conventional gap-type atomic switches that use a vacuum gap and Ag2+δS, which has restricted their practical use. In this study, we developed a new, easy to fabricate gap-type atomic switch that incorporates a molecular layer as a gap and Ta2O5 as an ionic transfer material. This molecular gap-type atomic switch operates in a manner that is similar to conventional vacuum gap-type atomic switches. We also demonstrate stochastic operations using the aforementioned molecular gap-type atomic switches. These results indicate a higher potential for the practical use of gap-type atomic switches.

[1]  Theoretical investigation of kinetics of a Cu2S-based gap-type atomic switch , 2011 .

[2]  Hisashi Shima,et al.  Resistive Random Access Memory (ReRAM) Based on Metal Oxides , 2010, Proceedings of the IEEE.

[3]  T. Hasegawa,et al.  Controlling the Synaptic Plasticity of a Cu2S Gap‐Type Atomic Switch , 2012 .

[4]  Rainer Waser,et al.  Switching kinetics of electrochemical metallization memory cells. , 2013, Physical chemistry chemical physics : PCCP.

[5]  T. Hasegawa,et al.  Short-term plasticity and long-term potentiation mimicked in single inorganic synapses. , 2011, Nature materials.

[6]  T. Hasegawa,et al.  Atomic Switch: Atom/Ion Movement Controlled Devices for Beyond Von‐Neumann Computers , 2012, Advanced materials.

[7]  Qing Wu,et al.  A novel true random number generator based on a stochastic diffusive memristor , 2017, Nature Communications.

[8]  A. Thomas,et al.  The Memristive Magnetic Tunnel Junction as a Nanoscopic Synapse‐Neuron System , 2012, Advanced materials.

[9]  Takuro Tamura,et al.  Material dependence of switching speed of atomic switches made from silver sulfide and from copper sulfide , 2007 .

[10]  J. Yang,et al.  Memristive switching mechanism for metal/oxide/metal nanodevices. , 2008, Nature nanotechnology.

[11]  T. Hasegawa,et al.  Nanometer-scale switches using copper sulfide , 2003 .

[12]  K. Terabe,et al.  Forming and switching mechanisms of a cation-migration-based oxide resistive memory , 2010, Nanotechnology.

[13]  Wei Yang Lu,et al.  Nanoscale memristor device as synapse in neuromorphic systems. , 2010, Nano letters.

[14]  Takeo Ohno,et al.  Memristive operations demonstrated by gap-type atomic switches , 2011 .

[15]  Masakazu Aono,et al.  On-demand nanodevice with electrical and neuromorphic multifunction realized by local ion migration. , 2012, ACS nano.

[16]  C. Wright,et al.  Beyond von‐Neumann Computing with Nanoscale Phase‐Change Memory Devices , 2013 .

[17]  J. Grollier,et al.  A ferroelectric memristor. , 2012, Nature materials.

[18]  R. Waser,et al.  Nanoscale cation motion in TaO(x), HfO(x) and TiO(x) memristive systems. , 2016, Nature nanotechnology.

[19]  Andrew S. Cassidy,et al.  A million spiking-neuron integrated circuit with a scalable communication network and interface , 2014, Science.

[20]  T. Hasegawa,et al.  Conductance quantization and synaptic behavior in a Ta2O5-based atomic switch , 2012, Nanotechnology.

[21]  L. Chua.  Memristor-The missing circuit element , 1971 .

[22]  D. Stewart,et al.  The missing memristor found , 2008, Nature.

[23]  Kazuyuki Aihara,et al.  A CMOS Spiking Neural Network Circuit with Symmetric/Asymmetric STDP Function , 2009, IEICE Trans. Fundam. Electron. Commun. Comput. Sci..

[24]  R. Waser,et al.  Atomically controlled electrochemical nucleation at superionic solid electrolyte surfaces. , 2012, Nature materials.

[25]  R. Waser,et al.  Redox Reactions at Cu,Ag/Ta2O5 Interfaces and the Effects of Ta2O5 Film Density on the Forming Process in Atomic Switch Structures , 2015 .

[26]  K. Terabe,et al.  Quantized conductance atomic switch , 2005, Nature.

[27]  R. Hesper,et al.  One-atom point contacts. , 1993 .

[28]  T. Hasegawa,et al.  Learning Abilities Achieved by a Single Solid‐State Atomic Switch , 2010, Advanced materials.

[29]  Yukihito Kondo,et al.  Quantized conductance through individual rows of suspended gold atoms , 1998, Nature.

[30]  Farnood Merrikh-Bayat,et al.  Training and operation of an integrated neuromorphic network based on metal-oxide memristors , 2014, Nature.