1. A memristive device ( 200 ) comprising: a first electrode ( 104 ); a second electrode ( 102 ); and a junction ( 106 ), said junction being interposed between said first electrode ( 104 ) and said second electrode ( 102 ), said junction ( 106 ) comprising: a semiconductor matrix ( 230 ); and particles ( 240 ) embedded in said semiconductor matrix ( 230 ), said particles ( 240 ) being configured to hold a selectable level of electrical charge, said electrical charge controlling the amount of current flowing through said junction ( 106 ) for a given reading voltage.