  We demonstrate trapping of electrons in a millimeter-sized quadrupole Paul
trap driven at 1.6~GHz in a room-temperature ultra-high vacuum setup. Cold
electrons are introduced into the trap by ionization of atomic calcium via
Rydberg states and stay confined by microwave and static electric fields for
several tens of milliseconds. A fraction of these electrons remain trapped
longer and show no measurable loss for measurement times up to a second.
Electronic excitation of the motion reveals secular frequencies which can be
tuned over a range of several tens to hundreds of MHz. Operating a similar
electron Paul trap in a cryogenic environment may provide a platform for
all-electric quantum computing with trapped electron spin qubits.
