Rather, “QQE with a Negative Interest Rate” further boosts the effects of existing policy measures by directly pushing down the short-end of the yield curve. In this sense, it can be called “enhanced QQE.” As I mentioned earlier, in the debate on monetary policy, the zero lower bound on nominal interest rates has traditionally been regarded as insurmountable.
Since a negative interest rate implies that the borrower receives interest while the lender has to pay interest, it is something that under normal circumstances is highly unlikely.