CRC Concise Encyclopedia of Nanotechnology

We are today facing a severe power consumption crisis, due to many factors: increase of worldwide energy consumption (by 40% in the last 20 years), cost of energy, climate warming, pollution, and restricted energy reserve. In this global scenario, electronics/information and communication technologies (ICT) is becoming a major player because a signicant part of the energy consumption (15% of electricity consumption today; but it is estimated to increase threefold in the next 20 years) is related to ICT systems. In addition, the battery lifetimes are not sufcient for the increasing needs of new mobile devices, and we need to develop future autonomous ultra-low-power (ULP) systems.