Continuing size reduction in mesoscopic and nanoscopic electronic, photonic, and plasmonic devices makes the employment of quantum physics (QP) and quantum electrodynamics (QED) inevitable. Engineers at the forefront of these fields increasingly need to have a working knowledge of QP and, more importantly, feel confident to manoeuver through the intricate calculations involved. However, electrical engineers and applied physicists are typically unfamiliar with the sophisticated mathematical apparatus in QP and QED, which is generally perceived to be formidably abstract.

• Chapter 1: The tale of "1" and "x"
• Chapter 2: The resolution of identity
• Chapter 3: Operator gymnastic
• Chapter 4: Generalized creation and annihilation operators