Charge sensing device with gate voltage selected to operate around the charge neutrality point and tune the quantum capacitance

A system comprising an electronic apparatus, wherein the electronic apparatus comprises:

• an electronic device comprising:
• a gate electrode structure;
• a dielectric structure arranged over said gate electrode structure;
• and
• a charge sensing structure comprising at least one 2-dimensional charge sensing layer configured to sense at least one of electrical charges and electrical charge density changes induced by an external physical quantity, and that is configured and arranged over said dielectric structure to provide a gate capacitance between the charge sensing structure and the gate electrode structure;
• wherein said charge sensing structure shows a quantum capacitance in series with said gate capacitance resulting in a total capacitance between the charge sensing structure and the gate electrode structure;
• a voltage detector electrically connected to the charge sensing structure or to the gate electrode structure, to detect an output voltage that is representative of said sensed electrical charges stored in said total capacitance;
• wherein the system further comprises a mechanism configured and arranged to apply a gate voltage to said gate electrode structure, wherein said gate voltage is selected to, both:
• make the electronic device operate around a most sensitive point of fermi level of the charge sensing structure;
• and
• tune the quantum capacitance to modify a sensitivity and dynamic range of the electronic device.